Milwaukee Instruments

Shop Milwaukee water testing meters and digital instruments at GroAqua. Our range includes pH testers, EC and TDS meters, dissolved oxygen meters and specialist water quality testing equipment for aquariums, hydroponics, aquaculture and water treatment.

From compact pocket testers to professional handheld meters, Milwaukee instruments help you measure important water parameters and monitor changing conditions. Explore replacement probes, calibration solutions and maintenance accessories to keep your testing equipment in good working order.


  • Milwaukee pH600AQ digital aquarium pH tester

    Milwaukee Milwaukee pH600AQ Digital pH Tester – Aquarium & Aquaculture Water Testing

    Maintain better water quality with the Milwaukee pH600AQ Digital pH Tester, a compact and easy-to-use instrument designed specifically for aquarium owners and aquaculture professionals. Accurately monitoring pH is essential for maintaining a healthy aquatic environment. Whether you're managing a freshwater aquarium, marine system, fish breeding setup or commercial aquaculture operation, the Milwaukee pH600AQ makes checking water pH quick and straightforward. Replacing traditional pH test strips and colour-based testing kits, this digital pH meter provides an easy-to-read LCD display and reliable measurements to help you keep water conditions within your desired range. Key Features & Benefits Designed for Aquariums & Aquaculture: Ideal for monitoring water pH in fish tanks, aquariums and aquaculture systems. Accurate Digital Measurements: ±0.1 pH accuracy for dependable water quality monitoring. Wide Measurement Range: Measures pH from 0.0 to 14.0, suitable for a wide variety of water testing applications. Simple One-Point Calibration: Easy manual calibration using the adjustment trimmer on the back of the tester. Clear LCD Display: Quickly view pH readings without interpreting colour charts or test strips. Compact & Portable: Lightweight pocket-sized design for convenient routine water testing. Long Battery Life: Up to approximately 700 hours of operation. Why Monitor Aquarium Water pH? pH is one of the most important water quality parameters in any aquarium or aquaculture system. Changes in pH can affect fish health, biological filtration and the overall stability of an aquatic environment. Regular pH testing helps you: Monitor water quality and identify changes early. Maintain suitable conditions for your fish. Monitor water parameters during aquarium maintenance. Check water conditions in fish breeding and aquaculture systems. Make informed decisions about water treatment and management. The Milwaukee pH600AQ provides a convenient way to monitor these changes as part of your regular water testing routine. Technical Specifications Specification Details Brand Milwaukee Instruments Model pH600AQ Measurement Parameter pH Measurement Range 0.0 – 14.0 pH Resolution 0.1 pH Accuracy ±0.1 pH Calibration Manual, 1-point Display Digital LCD Battery Type 3 × 1.5V alkaline Battery Life Up to approximately 700 hours Dimensions 150 × 30 × 24 mm Weight Approximately 85 g Easy to Use & Maintain Using the Milwaukee pH600AQ is straightforward: Remove the protective cap and switch on the tester. Immerse the electrode in your water sample, staying within the marked immersion level. Gently stir and allow the reading to stabilise. Read the pH measurement on the LCD display. Rinse the electrode after use and replace the protective cap. For reliable results, calibrate the tester regularly using fresh pH 7.01 calibration solution. Looking After Your pH Tester Proper electrode maintenance helps maintain measurement accuracy and extend sensor life. We recommend: Store the electrode with Milwaukee MA9015 storage solution in the protective cap. Never store the electrode in distilled or deionised water. Clean the electrode periodically using Milwaukee MA9016 cleaning solution. Calibrate the tester after cleaning or prolonged storage. Please note: Calibration solutions and electrode maintenance solutions are not included and should be purchased separately. Why Buy from GroAqua? At GroAqua, we supply specialist equipment and water monitoring solutions for aquaculture, aquariums and water treatment applications. The Milwaukee pH600AQ is a practical addition to any aquarium water testing kit, providing a simple and reliable way to keep track of an essential water quality parameter. Order your Milwaukee pH600AQ Digital pH Tester from GroAqua today.

    £27.58

  • Milwaukee MW600 PRO Dissolved Oxygen Meter (includes calibration solutions) Pocket Tester Milwaukee

    Milwaukee Milwaukee MW600 PRO Dissolved Oxygen Meter – Aquarium & Aquaculture Water Testing

    Monitor water quality with confidence using the Milwaukee MW600 PRO Portable Dissolved Oxygen Meter. Designed for reliable and straightforward dissolved oxygen (DO) measurement, this professional handheld meter is ideal for aquaculture, fish farming, aquarium management, koi ponds and environmental water testing. Dissolved oxygen is one of the most important parameters in aquatic environments. Fish, beneficial bacteria and other aquatic organisms depend on sufficient oxygen levels to maintain healthy conditions. The Milwaukee MW600 PRO provides fast, dependable dissolved oxygen readings through its polarographic oxygen probe, helping you monitor oxygen levels and make informed decisions about water quality management. Whether you're managing a commercial fish farm, operating an aquaculture facility or maintaining a freshwater aquarium or koi pond, the MW600 PRO offers a practical and cost-effective solution for routine dissolved oxygen testing. Key Features & Benefits Accurate Dissolved Oxygen Measurement: Measures dissolved oxygen from 0.0 to 19.9 mg/L with an accuracy of ±1.5% of full scale. Automatic Temperature Compensation: Automatically compensates for temperature variations between 0°C and 30°C. Two-Point Manual Calibration: Calibrates at zero oxygen and 100% air saturation for reliable measurements. Polarographic Oxygen Probe: Supplied with the MA840 reinforced dissolved oxygen probe featuring an oxygen-permeable PTFE membrane. Large Digital LCD Display: Easy-to-read measurements for convenient water quality monitoring. Portable & Lightweight: Compact handheld design suitable for fieldwork and routine testing. Extended Probe Cable: Supplied with a probe cable approximately 3 metres long, providing flexibility when testing tanks and ponds. Long Battery Life: Approximately 70 hours of continuous operation from one 9V alkaline battery. Replaceable Membrane System: Replaceable probe membranes and electrolyte solution help maintain reliable sensor performance. Why Measure Dissolved Oxygen in Aquariums & Aquaculture? Dissolved oxygen (DO) is essential for maintaining healthy aquatic environments. Insufficient oxygen can cause stress in fish, affect feeding behaviour and compromise overall fish health. In intensive aquaculture systems, oxygen monitoring is particularly important because stocking densities, feeding activity, temperature and biological processes can all influence oxygen availability. Regular dissolved oxygen testing helps you: Monitor oxygen levels in fish tanks and aquaculture systems. Identify potentially low oxygen conditions. Check the effectiveness of aeration and oxygenation equipment. Monitor water quality in koi ponds and freshwater aquariums. Assess oxygen levels during fish transport and holding operations. Support routine water quality management in commercial fish farms. The Milwaukee MW600 PRO makes it easier to monitor these important water quality parameters and maintain better oversight of your aquatic environment. Technical Specifications Specification Details Brand Milwaukee Instruments Model MW600 PRO Measurement Parameter Dissolved Oxygen (DO) Measurement Range 0.0 – 19.9 mg/L Resolution 0.1 mg/L Accuracy at 25°C ±1.5% Full Scale Calibration Manual, 2-point (zero and slope) Temperature Compensation Automatic, 0–30°C Probe MA840 Polarographic DO Probe Probe Membrane Oxygen-permeable PTFE Probe Cable Approximately 3 metres Operating Temperature 0–50°C Maximum Relative Humidity 95% Battery Type 1 × 9V alkaline Battery Life Approximately 70 hours Display Digital LCD Easy Calibration & Operation The Milwaukee MW600 PRO features a straightforward two-point calibration process to help maintain reliable dissolved oxygen measurements. Calibration is performed using: Zero oxygen calibration: Establishes the zero reference point. 100% air saturation calibration: Sets the measurement slope using air-saturated conditions. Once calibrated, the meter is ready for dissolved oxygen testing. The automatic temperature compensation feature adjusts measurements for temperature variations within its specified compensation range, making it suitable for routine monitoring in different aquatic environments. Probe Maintenance & Care The MW600 PRO uses a refillable polarographic probe that requires periodic maintenance to maintain measurement performance. For best results: Check the probe membrane regularly for damage, wrinkles or signs of wear. Replace damaged or worn membranes when necessary. Use fresh Milwaukee MA9071 electrolyte solution when refilling the probe. Ensure there are no air bubbles trapped inside the membrane during preparation. Keep the protective probe cap fitted when the meter is not in use. Calibrate the meter regularly and whenever required by your testing routine. Replacement membranes and electrolyte solution are available separately. What's Included? The Milwaukee MW600 PRO is supplied with the following standard equipment: Milwaukee MW600 PRO dissolved oxygen meter. MA840 polarographic dissolved oxygen probe. Spare probe membranes. Electrolyte solution for probe preparation. Calibration screwdriver. 9V alkaline battery. Instruction manual. Please note: Calibration solutions are not included with this product. Zero oxygen calibration solution (MA9070) is available separately. Why Buy from GroAqua? GroAqua supplies specialist water quality monitoring equipment for aquaculture, aquariums and water treatment applications. We understand the importance of reliable water quality monitoring in aquatic environments, from domestic aquariums and koi ponds to commercial fish farming operations. The Milwaukee MW600 PRO is an excellent addition to any aquaculture or aquarium water testing setup, providing a convenient and dependable way to monitor dissolved oxygen levels. Order your Milwaukee MW600 PRO Dissolved Oxygen Meter from GroAqua today.

    £219.99

  • Milwaukee pH51 Waterproof pH Tester with Replaceable Probe (FBA) Pocket Tester Milwaukee

    Milwaukee Milwaukee pH51 Waterproof Digital pH Tester – Replaceable Electrode

    Maintain accurate water quality monitoring with the Milwaukee pH51 Waterproof Digital pH Tester. Designed for reliability, durability and ease of use, this compact digital pH meter is ideal for aquarium owners, aquaculture professionals, hydroponics, horticulture and general water testing applications. The Milwaukee pH51 combines a waterproof IP65-rated housing with a replaceable double-junction pH electrode, making it a practical long-term investment for regular water quality monitoring. With an accuracy of ±0.1 pH and a measurement range of 0.0 to 14.0 pH, the pH51 provides straightforward digital measurements without the uncertainty of traditional colour-based test strips. Whether you're checking aquarium water, monitoring aquaculture systems or testing water in hydroponic growing environments, the Milwaukee pH51 offers a dependable and convenient solution. Key Features & Benefits Replaceable pH Electrode: Features a replaceable MA73600 double-junction electrode, extending the working life of the tester. Waterproof IP65 Housing: Designed to withstand water exposure and splashes during routine testing. Accurate pH Measurements: Provides ±0.1 pH accuracy for dependable water quality monitoring. Wide Measurement Range: Measures pH from 0.0 to 14.0, suitable for a wide range of water testing applications. Two-Point Manual Calibration: Allows calibration at two points using adjustment trimmers for improved measurement reliability. Large Digital LCD Display: Clear digital readings make monitoring pH quick and straightforward. Long Battery Life: Provides more than 1,500 hours of continuous operation under specified conditions. Compact & Lightweight: Pocket-sized design makes it convenient for everyday testing and field use. Double-Junction Electrode: Designed to provide reliable performance and help extend electrode service life. Ideal Applications The Milwaukee pH51 is suitable for a wide variety of water quality monitoring applications, including: Aquariums & Fish Tanks Regular pH testing helps aquarium owners monitor water conditions and maintain a suitable environment for freshwater and marine fish. Aquaculture & Fish Farming Monitor pH levels in fish tanks, hatcheries and aquaculture systems as part of a routine water quality management programme. Koi Ponds & Garden Ponds Check pond water pH to help maintain stable conditions for fish and aquatic life. Hydroponics Monitor nutrient solution pH to help maintain suitable growing conditions and nutrient availability for plants. Horticulture & Agriculture Useful for checking water and growing solution pH in horticultural and agricultural applications. Swimming Pools & General Water Testing A convenient digital solution for routine pH measurements across a range of water testing applications. Why Choose a Tester with a Replaceable Electrode? One of the main advantages of the Milwaukee pH51 is its replaceable pH electrode. Over time, all pH electrodes naturally deteriorate through regular use, contamination and ageing. This can result in slower response times and reduced measurement reliability. Unlike testers with permanently integrated electrodes, the pH51 allows the electrode to be replaced independently. The modular design provides several advantages: Extends the useful working life of the tester. Allows replacement of a worn or damaged electrode. Reduces the need to replace the complete instrument. Provides a more economical solution for regular pH monitoring. The replacement electrode for this model is the Milwaukee MA73600. Technical Specifications Specification Details Brand Milwaukee Instruments Model pH51 Measurement Parameter pH Measurement Range 0.0 – 14.0 pH Resolution 0.1 pH Accuracy ±0.1 pH at 25°C Calibration Manual, 2-point Electrode MA73600 double-junction Electrode Type Replaceable pH electrode Waterproof Rating IP65 Operating Temperature 0°C – 50°C Maximum Relative Humidity 100% Battery Type 3 × 1.5V alkaline Battery Life More than 1,500 hours Dimensions 165 × 30 × 30 mm Weight Approximately 80 g Simple Calibration & Operation The Milwaukee pH51 features straightforward manual two-point calibration. Calibration can be performed using appropriate pH buffer solutions: pH 7.01 buffer: Used to establish the neutral calibration point. pH 4.01 buffer: Used for acidic-range measurements. pH 10.01 buffer: Used for alkaline-range measurements. The tester has adjustment trimmers for the two calibration points, allowing you to calibrate the instrument according to your intended measurement range. To take a measurement: Remove the protective electrode cap. Switch on the Milwaukee pH51. Immerse the electrode in the water sample. Gently stir and allow the reading to stabilise. Read the pH measurement on the digital LCD display. Rinse the electrode after use and replace the protective cap. Electrode Maintenance & Care Correct electrode maintenance is essential for obtaining reliable pH measurements and extending electrode life. We recommend: Store the electrode with Milwaukee MA9015 storage solution. Never store the electrode in distilled or deionised water. Clean the electrode periodically using Milwaukee MA9016 cleaning solution. Calibrate the tester regularly and after electrode cleaning. Keep the protective cap fitted when the tester is not in use. Replace the MA73600 electrode when it becomes worn or its performance deteriorates. Suitable electrode maintenance products include: Milwaukee MA9015 Electrode Storage Solution. Milwaukee MA9016 Electrode Cleaning Solution. Milwaukee MA73600 Replacement pH Electrode. Milwaukee pH 4.01, 7.01 and 10.01 Calibration Solutions. What's Included? The Milwaukee pH51 is supplied with: Milwaukee pH51 waterproof pH tester. Replaceable MA73600 pH electrode. Batteries. Calibration solution. Calibration screwdriver. Protective packaging. Instruction manual. Why Buy from GroAqua? GroAqua supplies specialist water quality monitoring equipment for aquariums, aquaculture, horticulture and water treatment applications. We offer practical solutions for maintaining water quality, from everyday aquarium testing equipment to professional water monitoring instruments. The Milwaukee pH51 is an excellent choice for customers looking for a durable, waterproof digital pH tester with the added benefit of a replaceable electrode. Order your Milwaukee pH51 Waterproof Digital pH Tester from GroAqua today.

    £38.88

  • Milwaukee PH55 PRO Waterproof pH & Temperature Tester with ATC Handheld Meter Milwaukee

    Milwaukee Milwaukee pH55 PRO Waterproof pH & Temperature Tester – Replaceable Electrode

    Monitor water quality with confidence using the Milwaukee pH55 PRO Waterproof Digital pH and Temperature Tester. Designed for convenient, reliable water testing, this professional pocket-sized instrument measures both pH and temperature simultaneously, making it an excellent choice for aquarium owners, aquaculture professionals, hydroponics and general water quality monitoring. Featuring a waterproof IP65-rated housing, automatic temperature compensation (ATC) and an easily replaceable double-junction pH electrode, the Milwaukee pH55 PRO combines practical functionality with durable construction. Its large dual-level LCD display provides clear pH and temperature readings at the same time, helping you monitor important water parameters quickly and easily. With an extended pH measurement range of -2.0 to 16.0 and an accuracy of ±0.1 pH, the pH55 PRO offers a convenient alternative to traditional colour-based water testing kits. Whether you're maintaining a freshwater aquarium, monitoring an aquaculture system, managing a koi pond or checking hydroponic nutrient solutions, the Milwaukee pH55 PRO provides a practical solution for routine water testing. Key Features & Benefits Simultaneous pH & Temperature Measurement: Displays pH and temperature readings together on its large dual-level LCD screen. Automatic Temperature Compensation (ATC): Automatically compensates pH measurements for temperature variations. Waterproof IP65 Construction: Designed to withstand water exposure and splashes during routine testing. Replaceable pH Electrode: Features a replaceable Milwaukee Mi56P double-junction electrode, extending the useful life of the instrument. Wide pH Measurement Range: Measures from -2.0 to 16.0 pH, providing flexibility across different water testing applications. Accurate Measurements: Offers ±0.1 pH accuracy and ±0.5°C temperature accuracy. Automatic Calibration: Simple automatic one- or two-point calibration with two sets of pre-programmed buffer values. Large Dual-Level LCD: Easily view pH and temperature measurements simultaneously. Stability Indicator: Indicates when measurements have stabilised. Hold Function: Freezes the displayed reading for convenient recording. Long Battery Life: Provides approximately 300 hours of operation. Compact & Portable: Lightweight pocket-sized design suitable for everyday testing and field use. Ideal Applications The Milwaukee pH55 PRO is suitable for a wide range of water quality monitoring applications. Aquariums & Fish Tanks Regular pH and temperature monitoring helps aquarium owners maintain stable water conditions for freshwater and marine fish. Aquaculture & Fish Farming Monitor pH and temperature in fish tanks, hatcheries and aquaculture systems as part of a routine water quality management programme. Koi Ponds & Garden Ponds Check pond water pH and temperature to help maintain suitable environmental conditions for fish and aquatic life. Hydroponics Monitor the pH of nutrient solutions to help maintain appropriate growing conditions and nutrient availability for plants. Horticulture & Agriculture Useful for checking water and growing solution pH in horticultural and agricultural applications. Swimming Pools & Water Treatment A convenient digital instrument for monitoring pH as part of routine water quality management. Why Measure pH and Temperature Together? Water temperature influences pH measurements and is an important parameter in aquatic environments. The Milwaukee pH55 PRO incorporates automatic temperature compensation, adjusting the pH measurement according to the temperature of the sample within the instrument's specified operating range. The dual-level LCD also allows you to view both readings simultaneously. This makes it particularly useful for aquarium and aquaculture applications where understanding both pH and temperature helps provide a clearer picture of changing water conditions. Replaceable Double-Junction pH Electrode One of the main advantages of the Milwaukee pH55 PRO is its replaceable Mi56P double-junction pH electrode. All pH electrodes gradually deteriorate through normal use, ageing and contamination. Eventually, this can lead to slower response times and reduced measurement performance. The pH55 PRO features a modular electrode design, allowing the electrode to be replaced without having to purchase an entirely new meter. Benefits include: Extends the useful working life of the tester. Allows replacement of worn or damaged electrodes. Reduces the need to replace the complete instrument. Provides a practical long-term solution for regular water testing. The replacement electrode is the Milwaukee Mi56P, compatible with the pH55 and pH56 testers. Technical Specifications Specification Details Brand Milwaukee Instruments Model pH55 PRO Measurement Parameters pH & Temperature pH Measurement Range -2.0 to 16.0 pH pH Resolution 0.1 pH pH Accuracy ±0.1 pH Temperature Range -5.0 to 60.0°C Temperature Resolution 0.1°C / 0.1°F Temperature Accuracy ±0.5°C / ±1°F Temperature Compensation Automatic (ATC) Calibration Automatic, 1- or 2-point Buffer Options Standard and NIST buffer sets Electrode Milwaukee Mi56P Electrode Type Replaceable double-junction Waterproof Rating IP65 Display Dual-level LCD Stability Indicator Yes Hold Function Yes Battery Type 4 × 1.5V LR44 / A76 Battery Life Approximately 300 hours Auto Power Off After 8 minutes of inactivity Weight Approximately 100 g Easy Automatic Calibration The Milwaukee pH55 PRO features automatic one- or two-point calibration, making it straightforward to maintain measurement accuracy. Two sets of pre-programmed calibration buffers are available: Standard buffer set: pH 4.01 pH 7.01 pH 10.01 NIST buffer set: pH 4.01 pH 6.86 pH 9.18 The meter automatically recognises the calibration buffer values, helping simplify the calibration process. For routine aquarium and aquaculture water testing, two-point calibration using pH 7.01 and pH 4.01 is a suitable choice when monitoring predominantly neutral to acidic water conditions. Electrode Maintenance & Care Proper electrode maintenance is essential for maintaining reliable pH measurements and extending electrode life. We recommend: Store the electrode with Milwaukee MA9015 storage solution. Never store the electrode in distilled or deionised water. Clean the electrode periodically using Milwaukee MA9016 cleaning solution. Calibrate regularly and after cleaning or prolonged storage. Rinse the electrode with suitable rinse water between samples. Replace the electrode when response times become excessively slow or measurement performance deteriorates. Suitable maintenance products include: Milwaukee MA9015 Electrode Storage Solution. Milwaukee MA9016 Electrode Cleaning Solution. Milwaukee Mi56P Replacement pH Electrode. Milwaukee pH 4.01 Calibration Solution. Milwaukee pH 7.01 Calibration Solution. Milwaukee pH 10.01 Calibration Solution. What's Included? The standard Milwaukee pH55 PRO package includes: Milwaukee pH55 PRO pH and temperature tester. Replaceable Mi56P pH electrode. Protective electrode cap. pH 4.01 calibration solution sachet. pH 7.01 calibration solution sachet. LR44 batteries. Instruction manual. Protective packaging. Please check the supplied packaging configuration, as Milwaukee may offer different packaging options. Why Buy from GroAqua? GroAqua supplies specialist water quality monitoring equipment for aquariums, aquaculture, horticulture and water treatment applications. From everyday aquarium testing equipment to professional water monitoring instruments, we help customers find practical solutions for maintaining water quality. The Milwaukee pH55 PRO is an excellent choice for anyone looking for a waterproof digital pH tester with the added convenience of simultaneous temperature measurement and a replaceable electrode. Order your Milwaukee pH55 PRO Waterproof pH & Temperature Tester from GroAqua today.

    £69.90

  • Milwaukee MW101 PRO pH Meter Pocket Tester Milwaukee

    Milwaukee Milwaukee MW101 PRO Professional Digital pH Meter – High Accuracy

    Achieve accurate and reliable water quality measurements with the Milwaukee MW101 PRO Professional Digital pH Meter. Designed for demanding water testing applications, this portable instrument combines laboratory-grade measurement accuracy with a rugged, easy-to-use design. With an impressive accuracy of ±0.02 pH and a resolution of 0.01 pH, the MW101 PRO provides precise pH measurements across a wide range of applications. Supplied with the professional SE220 double-junction, gel-filled pH electrode, this meter is particularly suitable for aquarium water testing, aquaculture, fish farming, hydroponics, agriculture, brewing and general water quality monitoring. Its large digital LCD display makes readings easy to interpret, while the manual two-point calibration system helps maintain measurement accuracy. Whether you're monitoring water conditions in a commercial fish farm, maintaining an aquarium or testing nutrient solutions in hydroponic systems, the Milwaukee MW101 PRO offers dependable performance for regular pH measurement. Key Features & Benefits Professional Measurement Accuracy: Provides ±0.02 pH accuracy at 25°C for precise and dependable measurements. High Resolution: Displays measurements to 0.01 pH for more detailed monitoring of water conditions. Wide Measurement Range: Measures pH from 0.00 to 14.00, suitable for a wide variety of water testing applications. SE220 Professional pH Electrode: Supplied with a double-junction, gel-filled laboratory-grade electrode designed for reliable performance and low maintenance. Two-Point Manual Calibration: Allows calibration using offset and slope adjustment trimmers for improved measurement accuracy. Manual Temperature Compensation: Adjustable temperature compensation between 0°C and 50°C. Large Digital LCD Display: Provides clear, easy-to-read pH measurements. Portable & Rugged Design: Compact handheld instrument suitable for laboratory, workshop and field applications. Extended Probe Cable: The supplied electrode features an approximately 1-metre cable for convenient sample testing. Long Battery Life: Approximately 300 hours of continuous operation from a standard 9V battery. Automatic Power-Off: Helps conserve battery life when the instrument is not being used. Ideal Applications The Milwaukee MW101 PRO is designed for a wide variety of professional and everyday pH measurement applications. Aquariums & Fish Tanks Monitor aquarium water pH to help maintain suitable conditions for freshwater and marine fish. Regular testing helps identify changes in water chemistry and supports effective aquarium management. Aquaculture & Fish Farming Monitor pH levels in fish tanks, hatcheries, recirculating aquaculture systems (RAS) and commercial fish farming operations. Regular pH monitoring is an important part of maintaining stable water quality and supporting healthy aquatic environments. Koi Ponds & Garden Ponds Check pond water pH as part of routine water quality management to help maintain suitable conditions for fish and aquatic life. Hydroponics Measure nutrient solution pH to help maintain appropriate growing conditions and nutrient availability for plants. Agriculture & Horticulture Suitable for measuring pH in irrigation water, nutrient solutions and other agricultural water samples. Brewing & Food Production The MW101 PRO is also suitable for applications such as brewing and winemaking where monitoring pH is important for maintaining process consistency. Water Treatment & Environmental Testing A practical instrument for monitoring pH in water treatment processes, environmental samples and general water quality applications. Professional SE220 Double-Junction pH Electrode The Milwaukee MW101 PRO is supplied with the SE220 professional pH electrode. This laboratory-grade, double-junction, gel-filled electrode is designed to provide reliable measurements while reducing routine maintenance requirements associated with some refillable electrode designs. The double-junction construction provides an additional barrier between the reference system and the sample, making it a practical choice for a variety of water testing applications. Key electrode benefits include: Double-junction electrode construction. Gel-filled reference electrolyte. Low-maintenance design. Suitable for general laboratory and water testing applications. Approximately 1-metre connection cable. Replaceable electrode connected through a BNC connector. The electrode can be replaced independently if it becomes worn or damaged. Technical Specifications Specification Details Brand Milwaukee Instruments Model MW101 PRO Measurement Parameter pH Measurement Range 0.00 – 14.00 pH Resolution 0.01 pH Accuracy at 25°C ±0.02 pH Calibration Manual, 2-point Calibration Adjustment Offset and slope trimmers Temperature Compensation Manual Temperature Compensation Range 0°C – 50°C Electrode SE220 Electrode Type Double-junction, gel-filled Electrode Connection BNC Electrode Cable Approximately 1 metre Operating Temperature 0°C – 50°C Maximum Relative Humidity 95% Battery Type 1 × 9V alkaline Battery Life Approximately 300 hours Display Digital LCD Simple Two-Point Calibration The Milwaukee MW101 PRO features manual two-point calibration using offset and slope adjustment trimmers. For calibration, suitable pH buffer solutions are used to establish accurate reference points. Recommended calibration buffers include: pH 7.01: Neutral calibration point. pH 4.01: Acidic calibration point. pH 10.01: Alkaline calibration point. Two-point calibration helps maintain measurement accuracy across the intended testing range. For routine aquarium and aquaculture applications, calibration using pH 7.01 and pH 4.01 is a suitable starting point for predominantly neutral to acidic water measurements. Temperature Compensation The MW101 PRO features manual temperature compensation between 0°C and 50°C. Temperature compensation is important because pH electrode response changes with temperature. Unlike instruments with automatic temperature compensation, the MW101 PRO requires the user to adjust the temperature compensation setting to match the temperature of the sample. Please note that the MW101 PRO measures pH only and does not provide a digital temperature reading. Electrode Maintenance & Care Proper pH electrode maintenance is essential for maintaining measurement accuracy and extending electrode life. We recommend: Keep the electrode hydrated during storage. Store the electrode using Milwaukee MA9015 storage solution. Never store the electrode in distilled or deionised water. Clean the electrode periodically using Milwaukee MA9016 cleaning solution. Calibrate regularly and after cleaning or prolonged storage. Rinse the electrode between samples to prevent cross-contamination. Replace the electrode when response times become excessively slow or measurement performance deteriorates. Recommended maintenance products include: Milwaukee MA9015 Electrode Storage Solution. Milwaukee MA9016 Electrode Cleaning Solution. Milwaukee MA9007 pH 7.01 Calibration Solution. Milwaukee MA9004 pH 4.01 Calibration Solution. Milwaukee MA9010 pH 10.01 Calibration Solution. Milwaukee SE220 Replacement pH Electrode. What's Included? The standard Milwaukee MW101 PRO package includes: Milwaukee MW101 PRO digital pH meter. SE220 double-junction pH electrode. pH 7.01 calibration solution sachet. 9V alkaline battery. Calibration screwdriver. Instruction manual. Protective packaging. Why Buy from GroAqua? GroAqua supplies specialist water quality monitoring equipment for aquariums, aquaculture, horticulture and water treatment applications. We understand the importance of accurate and reliable water testing, from maintaining domestic aquariums to managing commercial aquaculture operations. The Milwaukee MW101 PRO is an excellent choice for customers looking for a professional portable pH meter with high measurement accuracy and a replaceable laboratory-grade electrode. Order your Milwaukee MW101 PRO Professional Digital pH Meter from GroAqua today.

    £133.32

  • Milwaukee MW600 PRO Dissolved Oxygen Meter (includes calibration solutions) Pocket Tester Milwaukee

    Milwaukee Milwaukee MW600 PRO Dissolved Oxygen Meter (includes calibration solutions)

    The Milwaukee MW600 PRO Portable Dissolved Oxygen meter is one of Milwaukee's most popular meters with its reliable and fast operation as well as its accuracy. The Milwaukee PRO DO Meter is preferred by people looking for lab level accuracy without the cost. The Milwaukee DO Meter is popular with everyone from field biologists and educators to fish farmers and koi pond owners. DESIGN FEATURES Fast, easy-to-read results with large digital LCD readout Repeatable, accuracy to ±1.5% FS Lightweight and portable Simple 2 point open air calibration (see video below) Uses MA840 reinforced polarographic probe with an oxygen-permeable polytetrafluorethylene (PTFE) membrane sensor 5 O-rings, membranes and one protective cap included 10 feet probe cable for extra flexibility when testing 70 hours of battery life with continuous use (battery included) with low battery warning CARE AND USE “OPEN AIR” CALIBRATION PROCEDURE 1. Remove the membrane Take the membrane off the end of the probe and dry the diode off. 2. Zero out the display Connect the probe to the base unit and turn the unit on. Your display should read 0.0. If it does not, go to the position “0” screw on the front of the unit with the screw driver provided and through the access hole make the unit display read 0.0. 3. Fill the membrane Go to the membrane and put the “O” ring inside the membrane on the shoulder at the base of the threads. Fill the membrane to just short of the “O” ring with MA9071 electrolyte solution. Be sure that there are no bubbles inside the membrane. (Air bubbles are the main cause of calibration failure) 4. Attach the membrane Screw the membrane on to the probe. 5. Let stablize Turn the meter on and hang the probe off the end of a table pointing down and let the unit display stabilize (this may take 5 to 15 minutes) 6. Adjust Push down and hold the “Cal” button on the front face of the meter and with the screwdriver go to the front Cal position “100%” and make the display read 100. You are now calibrated. EXTRA TIPS Watch for the membrane having wrinkles or stretch marks. If you see wrinkles, replace with a new membrane. Always use fresh electrolyte solution (MA9071). DOWNLOAD EXCEL WORKSHEET FOR TEMPERATURE COMPENSATION ON MW600 DO METER (XLS) Determine water temperature, insert reading from meter display, and this worksheet will automatically calculate a temperature-compensated DO reading for you.

    £236.15

  • Milwaukee EC59 PRO Waterproof 3-in-1 Conductivity / TDS & Temperature Tester with Replaceable Probe Pocket Tester Milwaukee

    Milwaukee Milwaukee EC59 PRO Waterproof EC / TDS / Temperature Meter – Replaceable Probe

    Monitor water quality quickly and accurately with the Milwaukee EC59 PRO Waterproof Conductivity, TDS and Temperature Meter. Designed for convenient everyday water testing, this compact 3-in-1 digital meter measures electrical conductivity (EC), total dissolved solids (TDS) and temperature, making it an excellent choice for aquariums, aquaculture, hydroponics, agriculture and general water quality monitoring. The Milwaukee EC59 PRO combines a waterproof IP65-rated housing with automatic temperature compensation (ATC), automatic calibration and a replaceable measurement probe. Its dual-level LCD display allows you to view conductivity or TDS measurements alongside the water temperature, helping you monitor important water quality parameters quickly and conveniently. With an EC measurement range of 0–3999 µS/cm and a TDS range of 0–2000 ppm, the EC59 PRO is particularly suitable for applications requiring low-to-medium conductivity water measurements. Whether you're maintaining an aquarium, monitoring aquaculture systems, checking hydroponic nutrient solutions or testing water treatment processes, the Milwaukee EC59 PRO provides a practical and reliable water testing solution. Key Features & Benefits 3-in-1 Water Quality Testing: Measures electrical conductivity (EC), total dissolved solids (TDS) and temperature using one compact instrument. Conductivity Measurement: Measures EC from 0 to 3999 µS/cm for monitoring dissolved ionic content in water. TDS Measurement: Measures total dissolved solids from 0 to 2000 ppm. Automatic Temperature Compensation (ATC): Automatically compensates conductivity measurements for temperature variations. Simultaneous Temperature Display: Displays water temperature alongside EC or TDS readings on the dual-level LCD. Waterproof IP65 Construction: Designed to withstand water exposure and splashes during routine testing. Replaceable Measurement Probe: Features a replaceable Milwaukee Mi59P probe, extending the useful life of the instrument. Automatic Calibration: Simple one-point calibration using the appropriate conductivity calibration solution. Adjustable TDS Conversion Factor: Allows the meter to accommodate different TDS conversion scales. Stability Indicator: Helps identify when readings have stabilised. Hold Function: Freezes the displayed reading for convenient recording. Compact & Portable: Lightweight pocket-sized design suitable for everyday testing and fieldwork. Battery Powered: Approximately 100 hours of operation from four LR44 batteries. Ideal Applications The Milwaukee EC59 PRO is suitable for a wide range of water quality monitoring applications. Aquariums & Fish Tanks Monitor electrical conductivity and TDS to help assess changes in dissolved ionic content and overall aquarium water conditions. Regular EC and TDS measurements can help identify changes in water composition, making the EC59 PRO a useful addition to an aquarium water testing kit. Aquaculture & Fish Farming Monitor conductivity and dissolved solids in fish tanks, hatcheries and aquaculture systems. EC measurements can help identify changes in water chemistry and support routine water quality management in commercial aquaculture operations. Hydroponics Electrical conductivity is an important measurement in hydroponic growing systems. The EC59 PRO allows growers to monitor nutrient solution conductivity and check whether nutrient concentrations remain within their desired operating range. Monitoring EC alongside temperature helps provide a better understanding of changing nutrient solution conditions. Agriculture & Horticulture Suitable for monitoring irrigation water, growing solutions and other agricultural water samples. Water Treatment Measure conductivity and TDS as part of routine water quality monitoring and treatment processes. Laboratory & General Water Testing A convenient portable instrument for checking conductivity, dissolved solids and temperature in a variety of water samples. Understanding EC and TDS Measurements The Milwaukee EC59 PRO measures electrical conductivity (EC) and converts this measurement into an estimated total dissolved solids (TDS) value. Although EC and TDS are closely related, they are not exactly the same measurement. Electrical Conductivity (EC) EC measures the ability of water to conduct electricity, which is influenced by the concentration of dissolved ions. Readings are displayed in microsiemens per centimetre (µS/cm). Conductivity monitoring is particularly useful in aquaculture, hydroponics and water treatment applications. Total Dissolved Solids (TDS) TDS is an estimate of the concentration of dissolved substances in water, normally displayed in parts per million (ppm). The EC59 PRO calculates TDS from its conductivity measurement using a selectable conversion factor. Different conversion factors can produce different TDS readings from the same EC measurement. The appropriate scale should therefore be selected according to your application and testing requirements. Automatic Temperature Compensation (ATC) Water conductivity changes with temperature, which can affect measurement results. The Milwaukee EC59 PRO incorporates automatic temperature compensation to adjust conductivity measurements according to the temperature of the sample. The temperature is displayed separately on the secondary LCD, allowing you to monitor both parameters during testing. The temperature compensation coefficient can also be adjusted to suit different measurement requirements. Replaceable Milwaukee Mi59P Probe One of the main advantages of the Milwaukee EC59 PRO is its replaceable Mi59P conductivity probe. Over time, measurement probes can become contaminated or deteriorate through regular use. The replaceable probe design allows you to change the sensing component without replacing the entire instrument. Benefits include: Extends the useful working life of the meter. Allows replacement of a worn or damaged probe. Reduces the need to purchase a completely new instrument. Provides a practical solution for regular water quality monitoring. The replacement probe is the Milwaukee Mi59P, compatible with the EC59 and EC60 testers. Technical Specifications Specification Details Brand Milwaukee Instruments Model EC59 PRO Measurement Parameters EC, TDS & Temperature EC Measurement Range 0–3999 µS/cm TDS Measurement Range 0–2000 ppm Temperature Range 0.0–60.0°C / 32.0–140.0°F EC Resolution 1 µS/cm TDS Resolution 1 ppm Temperature Resolution 0.1°C / 0.1°F EC Accuracy ±2% Full Scale TDS Accuracy ±2% Full Scale Temperature Accuracy ±0.5°C / ±1°F Calibration Automatic, 1-point EC Calibration Solution 1413 µS/cm Temperature Compensation Automatic (ATC) Temperature Compensation Coefficient Adjustable, β = 0.0–2.4%/°C TDS Conversion Factor Adjustable Probe Milwaukee Mi59P Probe Type Replaceable conductivity/TDS probe Waterproof Rating IP65 Display Dual-level LCD Battery Type 4 × 1.5V LR44 / A76 Battery Life Approximately 100 hours Automatic Power-Off After 8 minutes of inactivity Dimensions Approximately 200 × 38 mm Weight Approximately 100 g Easy Automatic Calibration The Milwaukee EC59 PRO features automatic one-point calibration to help maintain reliable conductivity measurements. Calibration is performed using a suitable conductivity calibration solution. For the EC59 PRO, the recommended calibration solution is: 1413 µS/cm Conductivity Calibration Solution The meter automatically recognises the calibration point and completes the calibration process. Regular calibration is recommended, particularly after replacing the probe, cleaning the sensor or when measurement accuracy is especially important. Because TDS is calculated from conductivity using a conversion factor, separate TDS calibration is not required. Probe Maintenance & Care Correct probe maintenance helps maintain measurement reliability and extend the working life of the instrument. We recommend: Rinse the probe with fresh water after every use. Remove any visible nutrient or mineral deposits. Clean the probe periodically using a suitable conductivity probe cleaning solution. Avoid allowing nutrient solutions or other residues to dry on the sensing surfaces. Calibrate regularly using fresh 1413 µS/cm conductivity calibration solution. Replace the Mi59P probe if it becomes damaged or measurement performance deteriorates. Fit the protective cap when the instrument is not in use. Recommended Accessories The following Milwaukee accessories are suitable for maintaining and calibrating the EC59 PRO: Milwaukee MA9061: 1413 µS/cm conductivity calibration solution. Milwaukee M10031B: 1413 µS/cm calibration solution sachets. Milwaukee MA9016: Cleaning solution. Milwaukee M10000B: Rinse solution sachets. Milwaukee Mi59P: Replacement EC/TDS probe. What's Included? The standard Milwaukee EC59 PRO package includes: Milwaukee EC59 PRO conductivity/TDS/temperature meter. Replaceable Mi59P measurement probe. Protective probe cap. 1413 µS/cm calibration solution sachet. Four LR44 batteries. Instruction manual. Protective packaging. Please check the supplied packaging configuration against your actual stock before publishing this list. Why Buy from GroAqua? GroAqua supplies specialist water quality monitoring equipment for aquariums, aquaculture, hydroponics and water treatment applications. From everyday aquarium water testing to professional water monitoring equipment, we help customers find practical solutions for maintaining water quality. The Milwaukee EC59 PRO is an excellent choice for customers looking for a compact, waterproof conductivity and TDS meter with the added convenience of temperature measurement and a replaceable probe. Order your Milwaukee EC59 PRO Waterproof EC/TDS/Temperature Meter from GroAqua today.

    £69.90

  • Last stock! Milwaukee MW803 MAX Waterproof Low Range 4-in-1 pH / EC / TDS/Temp Tester with Replaceable Probe Handheld Meter Milwaukee

    Milwaukee Milwaukee MW803 MAX Waterproof 4-in-1 pH / EC / TDS / Temperature Tester

    Monitor four essential water quality parameters with the Milwaukee MW803 MAX Waterproof 4-in-1 Digital Water Quality Tester. Designed for convenience, accuracy and versatility, this professional pocket-sized instrument measures pH, electrical conductivity (EC), total dissolved solids (TDS) and temperature using one compact device. The Milwaukee MW803 MAX is an excellent choice for aquarium owners, aquaculture professionals, hydroponic growers, horticultural businesses and water quality specialists looking for a convenient all-in-one testing solution. Featuring a waterproof IP65-rated housing, automatic temperature compensation (ATC), automatic calibration and a replaceable combination probe, the MW803 MAX provides reliable measurements across a wide range of water testing applications. Its large dual-level LCD displays pH, EC or TDS readings alongside temperature, allowing you to monitor important water quality parameters quickly and easily. With a pH measurement accuracy of ±0.05 pH, the MW803 MAX combines professional measurement performance with straightforward operation. Key Features & Benefits 4-in-1 Water Quality Testing: Measures pH, electrical conductivity (EC), total dissolved solids (TDS) and temperature using one instrument. High-Accuracy pH Measurement: Provides ±0.05 pH accuracy with a resolution of 0.01 pH. Electrical Conductivity Measurement: Measures EC from 0 to 3999 µS/cm, making it suitable for low-to-medium conductivity applications. TDS Measurement: Measures total dissolved solids from 0 to 2000 ppm. Automatic Temperature Compensation: Automatically compensates pH and conductivity measurements for temperature variations. Waterproof IP65 Construction: Designed to withstand water exposure and splashes during routine testing. Replaceable Combination Probe: Features the Milwaukee MI60P replacement probe, extending the useful working life of the instrument. Automatic Calibration: Simple automatic one- or two-point pH calibration and one-point EC calibration. Multiple Calibration Points: Recognises five memorised pH calibration buffer values. Dual-Level LCD Display: Shows measurement readings alongside water temperature. Stability Indicator: Helps identify when measurements have stabilised. Hold Function: Freezes displayed readings for convenient recording. Selectable TDS Conversion Factor: Allows the TDS conversion scale to be adjusted to suit different applications. Compact & Lightweight: Portable pocket-sized design weighing approximately 100 g. Long Battery Life: Approximately 100 hours of continuous operation. Ideal Applications The Milwaukee MW803 MAX is suitable for a wide range of water quality monitoring applications. Aquariums & Fish Tanks Monitor pH, conductivity, TDS and temperature to help maintain stable aquarium water conditions. Regular testing helps identify changes in water chemistry and provides a better understanding of overall aquarium water quality. The ability to monitor four parameters using one instrument makes the MW803 MAX a useful addition to any serious aquarium maintenance setup. Aquaculture & Fish Farming Water quality monitoring is essential in commercial fish farming and aquaculture operations. The MW803 MAX allows operators to monitor pH, conductivity, dissolved solids and temperature in fish tanks, hatcheries and recirculating aquaculture systems (RAS). Regular measurements help identify changes in water conditions and support effective water quality management. Hydroponics Electrical conductivity and pH are two particularly important parameters in hydroponic growing systems. The MW803 MAX allows growers to monitor nutrient solution pH and EC while also checking temperature and estimated TDS. This makes it a practical all-in-one instrument for monitoring hydroponic nutrient solutions and maintaining consistent growing conditions. Horticulture & Agriculture Monitor irrigation water, nutrient solutions and other agricultural water samples. The combination of pH, EC, TDS and temperature measurements provides useful information for managing growing environments. Koi Ponds & Garden Ponds Monitor important water parameters to help maintain suitable conditions for fish and aquatic life. Water Treatment & Environmental Monitoring Suitable for routine water quality checks in water treatment applications, environmental testing and general industrial water monitoring. Understanding the Four Measurements The Milwaukee MW803 MAX combines four important water quality measurements in one instrument. 1. pH – Acidity & Alkalinity pH measures how acidic or alkaline water is. Monitoring pH is important in aquariums, aquaculture and hydroponics because changing pH conditions can influence aquatic organisms, biological processes and nutrient availability. Measurement range: 0.00–14.00 pH. 2. EC – Electrical Conductivity Electrical conductivity measures the ability of water to conduct electricity, which is influenced by the concentration of dissolved ions. EC is particularly useful in hydroponics and aquaculture for monitoring changes in dissolved ionic content. Measurement range: 0–3999 µS/cm. 3. TDS – Total Dissolved Solids TDS estimates the concentration of dissolved substances in water, typically displayed in parts per million (ppm). The MW803 MAX calculates TDS from its conductivity measurement using a selectable conversion factor. Measurement range: 0–2000 ppm. 4. Temperature Water temperature is an important parameter in aquatic environments and hydroponic growing systems. The MW803 MAX measures temperature and displays it alongside the selected pH, EC or TDS reading. Measurement range: 0.0–50.0°C. Automatic Temperature Compensation (ATC) Temperature can influence both pH electrode response and electrical conductivity measurements. The Milwaukee MW803 MAX incorporates automatic temperature compensation to adjust measurements according to the temperature of the sample. An exposed temperature sensor positioned close to the measurement probes provides a fast response and helps improve temperature-compensated readings. The temperature is displayed on the secondary LCD, allowing you to monitor both measurements simultaneously. Replaceable Milwaukee MI60P Combination Probe One of the major advantages of the Milwaukee MW803 MAX is its replaceable MI60P combination probe. The probe incorporates the sensing components required for pH, conductivity and temperature measurement. The pH electrode uses a double-junction design, helping provide reliable performance and reducing routine maintenance requirements. The replaceable probe offers several advantages: Extends the useful working life of the instrument. Allows replacement of worn or damaged sensing components. Avoids the need to replace the complete tester when the probe deteriorates. Provides a more economical long-term solution for regular water testing. The replacement probe is the Milwaukee MI60P, compatible with both the MW803 MAX and MW804 MAX. Technical Specifications Specification Details Brand Milwaukee Instruments Model MW803 MAX Measurement Parameters pH, EC, TDS & Temperature pH Measurement Range 0.00–14.00 pH pH Resolution 0.01 pH pH Accuracy ±0.05 pH EC Measurement Range 0–3999 µS/cm EC Resolution 1 µS/cm EC Accuracy ±2% Full Scale TDS Measurement Range 0–2000 ppm TDS Resolution 1 ppm TDS Accuracy ±2% Full Scale TDS Conversion Factor Adjustable, 0.45–1.00 Temperature Range 0.0–50.0°C / 32.0–122.0°F Temperature Resolution 0.1°C / 0.1°F Temperature Accuracy ±0.5°C / ±1°F Temperature Compensation Automatic (ATC) Temperature Compensation Coefficient Adjustable, 0.0–2.4%/°C pH Calibration Automatic, 1- or 2-point EC Calibration Automatic, 1-point pH Calibration Buffers pH 4.01, 6.86, 7.01, 9.18 and 10.01 EC Calibration Solution 1413 µS/cm Probe Milwaukee MI60P Probe Type Replaceable combination probe Waterproof Rating IP65 Display Dual-level LCD Stability Indicator Yes Hold Function Yes Operating Temperature 0–50°C Maximum Relative Humidity 100% Battery Type 4 × 1.5V LR44 / A76 Battery Life Approximately 100 hours Automatic Power-Off After 8 minutes of inactivity Dimensions Approximately 200 × 38 mm Weight Approximately 100 g Easy Automatic Calibration The Milwaukee MW803 MAX features automatic calibration to help maintain measurement accuracy. pH Calibration The instrument supports automatic one- or two-point pH calibration. It recognises five memorised calibration buffer values: pH 4.01 pH 6.86 pH 7.01 pH 9.18 pH 10.01 Two-point calibration is recommended for greater accuracy across your intended measurement range. EC Calibration The EC measurement can be calibrated using a suitable conductivity calibration solution. For the MW803 MAX, the recommended calibration solution is: 1413 µS/cm Conductivity Calibration Solution. The instrument automatically recognises the calibration point and completes the calibration process. Understanding EC and TDS Conversion Although EC and TDS are closely related, they are different measurements. EC measures electrical conductivity, while TDS estimates the concentration of dissolved substances in water. The MW803 MAX converts EC measurements into estimated TDS values using an adjustable conversion factor between 0.45 and 1.00. Different conversion factors can produce different TDS readings from the same EC measurement. This is particularly important in hydroponics and aquaculture, where different measurement scales may be used. For consistent monitoring, always use the same conversion factor when comparing TDS readings over time. Probe Maintenance & Care Proper maintenance is essential for maintaining accurate measurements and extending the life of the MI60P combination probe. We recommend: Store the pH electrode using Milwaukee MA9015 electrode storage solution. Never store the pH electrode in distilled or deionised water. Clean the probe regularly using suitable Milwaukee MA9016 cleaning solution. Rinse the probe with fresh water after every measurement. Avoid allowing nutrient solutions or mineral deposits to accumulate on the sensing surfaces. Calibrate after cleaning and whenever measurement performance needs checking. Replace the MI60P probe when it becomes damaged or its performance deteriorates. Keep the protective cap fitted when the tester is not in use. Recommended Accessories The following Milwaukee accessories are suitable for maintaining and calibrating the MW803 MAX: Milwaukee MI60P: Replacement combination pH/EC/TDS probe. Milwaukee MA9015: Electrode storage solution. Milwaukee MA9016: Electrode cleaning solution. Milwaukee MA9004: pH 4.01 calibration solution. Milwaukee MA9007: pH 7.01 calibration solution. Milwaukee MA9061: 1413 µS/cm conductivity calibration solution. Milwaukee M10031B: 1413 µS/cm calibration solution sachets. Milwaukee M10000B: Rinse solution sachets. What's Included? The standard Milwaukee MW803 MAX package includes: Milwaukee MW803 MAX 4-in-1 water quality tester. Replaceable MI60P combination probe. Protective probe cap. pH 4.01 calibration solution sachet. pH 7.01 calibration solution sachet. 1413 µS/cm conductivity calibration solution sachet. Four LR44 batteries. Instruction manual. Protective packaging. Why Buy from GroAqua? GroAqua supplies specialist water quality monitoring equipment for aquariums, aquaculture, hydroponics, horticulture and water treatment applications. From everyday aquarium testing equipment to professional water monitoring instruments, we help customers find practical solutions for maintaining water quality. The Milwaukee MW803 MAX is an excellent choice for anyone looking for a versatile, waterproof water quality tester capable of measuring four essential parameters in one compact instrument. Order your Milwaukee MW803 MAX Waterproof 4-in-1 Water Quality Tester from GroAqua today.

    £174.85

  • Milwaukee CD601 Digital Conductivity Pen (EC) Pocket Tester Milwaukee

    Milwaukee Milwaukee CD601 Digital Conductivity (EC) Pocket Tester

    The Milwaukee CD601 is a compact, easy-to-use electrical conductivity (EC) tester for checking water quality in aquariums, aquaculture systems, pools, water treatment applications and more. Designed for quick, routine measurements, the CD601 measures conductivity across a range of 0 to 1,990 µS/cm. Its automatic temperature compensation helps account for temperature differences during testing, while straightforward one-point calibration makes it simple to maintain reliable measurements. Whether you are monitoring aquarium water, checking freshwater systems or carrying out routine water-quality checks, the CD601 provides a convenient way to keep track of conductivity. Key Features 0–1,990 µS/cm EC range – suitable for low-to-moderate conductivity water applications. 10 µS/cm resolution – displays conductivity changes in practical increments. Automatic Temperature Compensation (ATC) – compensates for temperature variation from 5 to 50°C. Simple one-point calibration – manual calibration using the calibration trimmer and the appropriate standard solution. Compact pocket-sized design – convenient for routine checks and portable use. Factory calibrated – supplied ready for use, with the ability to recalibrate when required. Long battery life – approximately 300 hours of use from four included 1.5V alkaline batteries. Why Measure Electrical Conductivity? Electrical conductivity indicates how readily water conducts an electrical current, which is influenced by the concentration of dissolved ions. Regular EC measurements can help aquarium keepers and aquatic professionals monitor changes in water composition, compare water sources and check consistency during water preparation or treatment. For aquaculture and aquarium applications, conductivity readings can be useful as part of a wider water-quality monitoring routine. EC should be considered alongside other relevant parameters, such as pH, temperature, dissolved oxygen and ammonia. Automatic Temperature Compensation Water conductivity changes with temperature. The CD601 features automatic temperature compensation from 5 to 50°C, helping to make readings more consistent when sample temperatures vary. Simple Calibration The CD601 can be recalibrated at a single point using the recommended Milwaukee M10031B 1413 µS/cm conductivity calibration solution. Calibration is performed manually using the adjustment trimmer and a small screwdriver. Regular calibration helps maintain confidence in measurements, particularly where the tester is used frequently. EC and TDS: Understanding the Difference The CD601 measures electrical conductivity (EC) in µS/cm. It does not directly measure total dissolved solids (TDS) in ppm. EC readings can be used to estimate TDS, but the conversion depends on the factor or scale being applied. Different conversion factors can produce different ppm values from the same conductivity reading. For accurate water analysis, it is important to understand which measurement your application requires. If you need a dedicated TDS tester with a direct ppm reading, consider the Milwaukee CD600 instead. Care and Maintenance To help maintain reliable performance: Rinse the sensing area with clean water after each use. Avoid allowing nutrient deposits or other residue to build up on the sensor. Keep the protective cap in place when the tester is not being used. Calibrate periodically, and whenever readings become questionable. Use fresh calibration solution for best results. Technical Specifications Specification Details Model Milwaukee CD601 Measurement Electrical conductivity (EC) Measuring range 0–1,990 µS/cm Resolution 10 µS/cm Accuracy ±2% full scale Calibration Manual, one point Recommended calibration solution Milwaukee M10031B, 1413 µS/cm Temperature compensation Automatic, 5–50°C Operating environment 5–50°C, up to 95% RH Power supply 4 × 1.5V alkaline batteries Battery life Approximately 300 hours Dimensions 150 × 30 × 24 mm Weight 85 g Supplied with Milwaukee CD601 conductivity tester Protective cap Calibration screwdriver Batteries Instruction manual A practical, economical EC tester for routine water conductivity checks. The Milwaukee CD601 combines simple operation, automatic temperature compensation and convenient pocket-sized portability for aquarium, aquaculture and general water-quality applications.

    £27.59

  • Milwaukee CD600 Digital Total Dissolved Solids Pen (TDS) Pocket Tester Milwaukee

    Milwaukee Milwaukee CD600 Digital TDS Meter – Pocket Water Tester

    The Milwaukee CD600 Digital TDS Meter is a compact, economical tester designed to measure total dissolved solids (TDS) in water. With a measurement range of 0–1,990 ppm, it provides a convenient way to monitor dissolved-solids levels in aquariums, hydroponic nutrient solutions, horticultural systems and water-treatment applications. Easy to operate and small enough to carry in your pocket, the CD600 is ideal for routine water checks where a quick TDS reading is required. Its automatic temperature compensation helps account for temperature differences, while simple one-point calibration allows the meter to be recalibrated when necessary. Whether you are checking aquarium water, monitoring nutrient solutions or assessing the performance of water filtration systems, the Milwaukee CD600 offers a straightforward approach to everyday TDS testing. Key Features 0–1,990 ppm measuring range – suitable for low-to-moderate TDS applications. 10 ppm resolution – displays readings in practical 10 ppm increments. ±2% full-scale accuracy – provides dependable measurements for routine monitoring. Automatic Temperature Compensation (ATC) – compensates for temperature variation from 5 to 50°C. Simple one-point calibration – manual calibration using the adjustment trimmer. Factory calibrated – ready for use, with the option to recalibrate when required. Pocket-sized design – lightweight and convenient for portable water testing. Battery powered – uses four 1.5V alkaline batteries. Why Measure Total Dissolved Solids? Total dissolved solids (TDS) describes the concentration of dissolved substances in water, including dissolved salts and minerals. TDS measurements are commonly used to monitor water composition and identify changes over time. Regular testing can help: Monitor dissolved-solids levels in aquarium and freshwater systems. Check nutrient-solution consistency in hydroponic applications. Compare water quality before and after filtration. Monitor changes in water sources. Maintain consistent water conditions as part of a wider testing routine. For aquariums and aquaculture systems, TDS can provide useful supporting information about water composition. It should not be used as a substitute for testing individual parameters such as pH, ammonia, nitrite, nitrate or dissolved oxygen. Automatic Temperature Compensation Temperature can influence conductivity measurements and, consequently, calculated TDS readings. The Milwaukee CD600 features automatic temperature compensation from 5 to 50°C, helping to account for temperature variation during measurement. This makes it practical for routine testing where samples may not always be at the same temperature. Simple One-Point Calibration The CD600 is factory calibrated and can be recalibrated manually using a suitable TDS calibration solution. For this model, Milwaukee specifies the M10032B 1382 ppm TDS calibration solution. Calibration is performed using the adjustment trimmer and a small screwdriver. Regular calibration helps maintain confidence in readings, particularly when the tester is used frequently. Understanding TDS and EC TDS and electrical conductivity (EC) are closely related, but they are not the same measurement. EC measures how readily water conducts electricity, while TDS meters use conductivity to estimate the concentration of dissolved solids and display the result in parts per million (ppm). Different conversion scales are used, including the 500, 650 and 700 scales. As a result, two TDS meters using different conversion factors may display different ppm readings for the same water sample. For consistent monitoring, use the same measurement scale when comparing readings over time. Care and Maintenance To help maintain reliable performance: Rinse the sensing area with clean tap or deionised water after every use. Remove any nutrient or mineral residue from the sensing area. Avoid touching the metal sensing elements. Replace the protective cap after use. Recalibrate periodically or whenever readings become questionable. Use fresh calibration solution and avoid contaminating the solution during calibration. Technical Specifications Specification Details Model Milwaukee CD600 Measurement Total Dissolved Solids (TDS) Measuring range 0–1,990 ppm Resolution 10 ppm Accuracy ±2% full scale Calibration Manual, one point Recommended calibration solution Milwaukee M10032B, 1382 ppm Temperature compensation Automatic, 5–50°C Operating environment 5–50°C, maximum 95% RH Power supply 4 × 1.5V alkaline batteries Battery life Approximately 300 hours Dimensions 150 × 30 × 24 mm Weight 85 g Supplied with Milwaukee CD600 digital TDS tester Protective cap Four 1.5V alkaline batteries A Convenient TDS Tester for Everyday Water Monitoring The Milwaukee CD600 combines simple operation, automatic temperature compensation and a practical 0–1,990 ppm range in a compact pocket-sized instrument. It is a useful choice for aquarium keepers, hydroponic growers and anyone who needs a straightforward way to monitor dissolved-solids levels in water.

    £27.59

  • Last stock! Milwaukee MW801 PRO 3-in-1 Low Range pH, EC, TDS Combo Meter with ATC Handheld Meter Milwaukee

    Milwaukee Milwaukee MW801 PRO 3-in-1 pH, EC & TDS Meter

    The Milwaukee MW801 PRO is a portable, professional water-quality meter that measures pH, electrical conductivity (EC) and total dissolved solids (TDS) using one integrated combination probe. Designed for freshwater applications, aquariums, aquaculture, hydroponics and nutrient-solution monitoring, the MW801 makes it easier to check three important water parameters without carrying separate instruments. Its replaceable SE600 combination probe incorporates pH, EC/TDS and temperature-sensing components. Automatic temperature compensation helps account for temperature variation during EC and TDS measurements, while simple manual calibration makes routine maintenance straightforward. With a low-range EC measurement capability of up to 1,990 µS/cm and TDS measurement up to 1,990 ppm, the MW801 PRO is particularly suitable for applications where monitoring relatively low dissolved-solids concentrations is important. Key Features Three measurements in one instrument – measures pH, electrical conductivity (EC) and total dissolved solids (TDS). Low-range EC measurement – measures conductivity from 0 to 1,990 µS/cm. Low-range TDS measurement – measures dissolved-solids levels from 0 to 1,990 ppm. Replaceable SE600 combination probe – combines pH, EC/TDS and temperature-sensing functions in one probe. Automatic Temperature Compensation (ATC) – compensates for temperature variation during EC and TDS measurements from 0 to 50°C. Manual one-point calibration – straightforward calibration for pH and EC/TDS. Large, easy-to-read display – clearly displays measurement results. Portable design – suitable for routine testing in the field, laboratory or workplace. Supplied with calibration solutions and battery – ready for setup and use. Three Important Water Measurements in One Meter The MW801 PRO combines three useful water-quality measurements in a single instrument. pH – Acidity and Alkalinity pH indicates how acidic or alkaline water is. Monitoring pH is important for aquarium management, aquaculture, hydroponics and water treatment, as changes can affect aquatic organisms, nutrient availability and water chemistry. The MW801 measures pH across a range of 0.0 to 14.0 pH. EC – Electrical Conductivity Electrical conductivity indicates how readily water conducts an electrical current. It is influenced by the concentration of dissolved ions, including salts and minerals. EC monitoring is useful when checking water sources, monitoring nutrient solutions and observing changes in dissolved ionic content. The MW801 measures EC from 0 to 1,990 µS/cm. TDS – Total Dissolved Solids TDS provides an estimated measurement of dissolved-solids concentration, displayed in parts per million (ppm). It is commonly used in water treatment, aquariums and hydroponic applications to monitor changes in dissolved-solids levels. The MW801 measures TDS from 0 to 1,990 ppm. One Combination Probe – Three Measurements The MW801 PRO is supplied with the SE600 combination probe, which incorporates pH, EC/TDS and temperature-sensing components. Using one probe for all three measurements makes routine testing more convenient and reduces the need to handle multiple separate electrodes. The SE600 is replaceable, allowing the probe to be changed when its performance deteriorates or it reaches the end of its service life. The probe features a double-junction pH electrode design and a fibre junction intended to help reduce contamination when testing nutrient and fertiliser solutions. Automatic Temperature Compensation Temperature affects electrical conductivity, so readings need to account for changes in sample temperature. The MW801 features automatic temperature compensation from 0 to 50°C for EC and TDS measurements. This helps provide more consistent readings when testing samples at different temperatures. Simple Calibration The MW801 PRO uses manual one-point calibration for pH and EC/TDS. For pH calibration, Milwaukee recommends using an appropriate buffer solution, such as pH 7.01 for measurements around neutral pH. For EC/TDS calibration, use the appropriate standard: M10031B – 1,413 µS/cm conductivity calibration solution M10032B – 1,382 ppm TDS calibration solution The meter's EC and TDS measurements are linked internally. Calibrating in either EC or TDS mode automatically calibrates the other measurement mode. Suitable Applications The Milwaukee MW801 PRO is suitable for a range of water-quality monitoring tasks, including: Aquariums: monitor pH, conductivity and TDS as part of routine water-quality checks. Aquaculture: monitor changes in water chemistry and dissolved ionic content. Hydroponics: check pH and nutrient-solution conductivity to support nutrient management. Aquaponics: monitor important water parameters in integrated fish and plant systems. Water treatment: assess changes in dissolved-solids levels and conductivity. Freshwater testing: measure pH, EC and TDS in freshwater samples. For aquariums and aquaculture, the MW801 is best used as part of a wider water-testing routine. It does not measure parameters such as ammonia, nitrite, nitrate or dissolved oxygen. Probe Care and Maintenance The combination probe is an important component of the MW801 and needs regular care to maintain reliable performance. Recommended maintenance: Rinse the probe with clean water after testing. Keep the pH sensing element hydrated using suitable electrode storage solution. Do not store the probe in distilled or deionised water. Clean the electrode periodically using an appropriate electrode cleaning solution. Calibrate after cleaning and whenever readings become questionable. Replace the probe when response time or measurement performance deteriorates. Milwaukee recommends MA9015 storage solution for pH electrode storage and MA9016 cleaning solution for electrode maintenance. Technical Specifications Specification Details Model Milwaukee MW801 PRO Measurements pH, EC and TDS pH range 0.0–14.0 pH pH resolution 0.1 pH pH accuracy ±0.2 pH EC range 0–1,990 µS/cm EC resolution 10 µS/cm EC accuracy ±2% full scale TDS range 0–1,990 ppm TDS resolution 10 ppm TDS accuracy ±2% full scale TDS conversion factor 0.5 Calibration Manual, one point Temperature compensation Automatic, 0–50°C Probe SE600 combination pH/EC/TDS probe Probe cable 1 m Operating environment 0–50°C; maximum 95% RH Power supply 1 × 9V alkaline battery Battery life Approximately 150 hours Meter dimensions 143 × 80 × 32 mm Weight Approximately 220 g, including battery Supplied With Milwaukee MW801 PRO meter SE600 combination pH/EC/TDS probe 20 mL pH 7.01 calibration solution 20 mL 1,413 µS/cm conductivity calibration solution 20 mL 1,382 ppm TDS calibration solution 9V alkaline battery Instruction manual A Versatile 3-in-1 Meter for Water Quality Monitoring The Milwaukee MW801 PRO combines pH, EC and TDS testing in one portable instrument. Its replaceable SE600 probe, automatic temperature compensation and straightforward calibration make it a practical choice for aquarium keepers, aquaculture professionals and hydroponic growers. Choose the MW801 PRO when you need a reliable way to monitor three important water parameters without carrying separate meters.

    £234.47

  • Last stock! Milwaukee MW11 Digital Total Chlorine Tester Pocket Tester Milwaukee

    Milwaukee Milwaukee MW11 Digital Total Chlorine Tester for Aquariums

    The Milwaukee MW11 Digital Total Chlorine Tester is a compact photometer designed to measure total chlorine in water. It is a useful instrument for aquarium keepers who want to check tap water, prepared replacement water and other freshwater sources before introducing them into an aquarium. Chlorine and chloramine are commonly used to disinfect municipal drinking water. However, these disinfectants can be harmful to fish, shrimp, corals and beneficial bacteria in aquarium filtration systems. The MW11 provides a quick digital measurement of total chlorine, helping you check whether your water treatment process has reduced residual chlorine to an acceptable level before using the water for aquarium maintenance. With a measuring range of 0.00 to 3.50 ppm, a resolution of 0.01 ppm and no visual colour matching required, the MW11 offers a convenient alternative to interpreting traditional colour-based test kits. Key Features Total chlorine measurement – measures total chlorine, including free and combined chlorine. Ideal for aquarium water preparation – check tap water and prepared replacement water before use. 0.00–3.50 ppm range – suitable for routine testing of water sources and treated water. 0.01 ppm resolution – displays readings in small increments. High measurement accuracy – ±0.03 ppm ±3% of reading at 25°C. Digital photometer – measures the colour reaction electronically, avoiding subjective visual colour comparison. No calibration required – ready for use with the supplied reagents. Compact and portable – convenient for aquarium rooms, fish facilities and water-testing work. Simple reagent-based testing – uses Milwaukee DPD powder reagents for total chlorine measurement. Why Test Total Chlorine in Aquarium Water? Chlorine-based disinfectants are widely used to make municipal water safe for human consumption. However, water that is suitable for drinking is not necessarily suitable for aquarium use without treatment. Residual chlorine can damage fish gill tissue and harm sensitive aquatic organisms. It can also affect the beneficial bacteria responsible for biological filtration. Some water supplies use chloramine, a disinfectant formed by combining chlorine and ammonia. Unlike free chlorine, chloramine can be more persistent and may not be removed simply by allowing water to stand. Testing total chlorine is therefore particularly useful when preparing aquarium water from a municipal supply. The MW11 helps you: Check incoming tap water before aquarium use. Verify the effectiveness of a dechlorination process. Test replacement water before carrying out water changes. Monitor water after carbon filtration or other treatment. Check water used in freshwater and marine aquarium preparation. Total Chlorine vs Free Chlorine Understanding the difference between free chlorine and total chlorine is important when preparing aquarium water. Free chlorine refers to chlorine disinfectant present in its free forms, such as hypochlorous acid and hypochlorite. Combined chlorine refers to chlorine that has reacted with ammonia or other nitrogen-containing compounds. Chloramine is an important example. Total chlorine includes both free chlorine and combined chlorine. This distinction matters because a test that measures only free chlorine may not identify all chlorine-based disinfectant remaining in the water. The MW11 is designed specifically to measure total chlorine, making it useful when checking water supplies that may contain chloramine. Digital Photometer – No Guesswork with Colour Charts The MW11 uses a DPD reagent reaction and an electronic optical measurement system. When the reagent reacts with total chlorine in the water sample, it produces a pink colour. The photometer measures the intensity of this colour using an LED light source and silicon photocell, then displays the result digitally in ppm. This avoids the need to visually compare a sample against a printed colour chart. The instrument uses an adaptation of USEPA Method 330.5. How to Test Aquarium Water with the MW11 The MW11 uses a simple sample-and-reagent procedure. Fill a clean sample cuvette with 10 mL of the water being tested. Place the cuvette into the tester and close the cover. Follow the instrument's zeroing procedure. Remove the cuvette and add one Milwaukee MI524 total chlorine powder reagent sachet. Replace the cap and gently shake for approximately 20 seconds. Return the cuvette to the tester. Allow the reaction time specified in the instrument procedure. Read the total chlorine result directly from the digital display. Always follow the supplied Milwaukee instruction manual for the complete measurement sequence and timing. What Should the Total Chlorine Reading Be for Aquarium Water? For aquarium water preparation, the objective is to achieve no detectable residual chlorine before adding the water to the aquarium. A reading of 0.00 ppm on the MW11 indicates that total chlorine is below the instrument's detectable reading at its displayed resolution. It does not prove the absolute absence of every chlorine compound. If a reading is detected after water treatment, do not assume the water is ready for aquarium use. Review the water-conditioning process and test again before introducing the water. For supplies treated with chloramine, use a conditioner specifically suitable for chloramine removal or treatment. Follow the manufacturer's instructions for the water conditioner and allow the recommended contact time before testing. Suitable Aquarium Applications The Milwaukee MW11 is particularly useful for: Freshwater aquariumsCheck tap water and replacement water before water changes to help prevent accidental introduction of residual disinfectants. Marine and reef aquariumsTest source water and prepared replacement water as part of a wider water-quality management routine. The MW11 measures total chlorine; it does not measure salinity, alkalinity or other reef-water parameters. Shrimp and sensitive fish systemsUse total chlorine testing as an additional precaution when preparing water for sensitive aquatic livestock. Aquaculture and fish facilitiesCheck incoming water and treated water used in fish-holding, hatchery and production systems. Water filtration systemsMonitor source and treated water to help assess chlorine removal performance. Reagents and Maintenance The MW11 requires Milwaukee MI524 total chlorine powder reagents for testing. The meter is supplied with six reagent sachets. Additional reagent packs are available separately: MI524-25 – total chlorine powder reagents, 25 tests. MI524-100 – total chlorine powder reagents, 100 tests. Keep the glass cuvettes clean and free from fingerprints, scratches and residue. Rinse them after use and wipe the outside with a suitable lint-free cloth before placing them in the instrument. Use fresh reagents and follow the prescribed sample volume and reaction time to maintain reliable results. Technical Specifications Specification Details Model Milwaukee MW11 Measurement Total chlorine Measuring range 0.00–3.50 ppm Resolution 0.01 ppm Accuracy ±0.03 ppm ±3% of reading at 25°C Typical EMC deviation ±0.01 ppm Measurement method Adaptation of USEPA Method 330.5 Reagent method DPD powder reagent Light source LED at 525 nm Light detector Silicon photocell Calibration No calibration required Sample volume 10 mL Operating environment 0–50°C, maximum 95% RH non-condensing Power supply 1 × 1.5V AAA battery Auto shut-off After 2 minutes of non-use Dimensions 87.5 × 63.7 × 35.2 mm Weight Approximately 65 g Supplied With Milwaukee MW11 digital total chlorine photometer Two sample cuvettes with caps Six total chlorine powder reagent sachets 1 × 1.5V AAA battery Instruction manual Important Information The MW11 measures total chlorine in a water sample. It does not remove chlorine or chloramine, and it is not a general-purpose aquarium water tester. For complete aquarium water-quality monitoring, use it alongside appropriate tests for pH, ammonia, nitrite, nitrate and other parameters relevant to your aquarium. Protect your aquarium before every water change. The Milwaukee MW11 provides a convenient digital way to check total chlorine in tap water and prepared aquarium replacement water before it reaches your fish and biological filter.

    £73.56

  • Last stock! Milwaukee MW10 Digital Free Chlorine Tester Pocket Tester Milwaukee

    Milwaukee Milwaukee MW10 Digital Free Chlorine Tester for Aquariums

    The Milwaukee MW10 Digital Free Chlorine Tester is a compact photometer designed to measure free chlorine in water. It is a useful instrument for aquarium keepers who want to check tap water, filtered water and prepared replacement water before introducing it into an aquarium. Chlorine is commonly used to disinfect municipal drinking water. Although this makes water suitable for human consumption, residual chlorine can be harmful to fish, shrimp, corals and the beneficial bacteria responsible for biological filtration. The MW10 provides a quick digital measurement of free chlorine, helping you monitor water-treatment processes and check for residual chlorine before aquarium use. With a measuring range of 0.00–2.50 ppm, a resolution of 0.01 ppm and an accuracy of ±0.03 ppm ±3% of the reading at 25°C, the MW10 offers a convenient alternative to traditional colour-comparison chlorine test kits. Key Features Free chlorine measurement – measures free chlorine in water. Ideal for aquarium water preparation – check source water and prepared replacement water. 0.00–2.50 ppm measuring range – suitable for routine free chlorine testing. 0.01 ppm resolution – displays readings in small increments. High measurement accuracy – ±0.03 ppm ±3% of reading at 25°C. Digital photometer technology – measures the colour reaction electronically, avoiding subjective visual comparison. No calibration required – ready for use with the supplied reagents. Compact and portable – convenient for aquarium rooms, fish facilities and water-testing work. Simple reagent-based testing – uses Milwaukee MI526 free chlorine powder reagents. Why Test Free Chlorine in Aquarium Water? Municipal water supplies commonly use chlorine-based disinfectants to control microorganisms and make drinking water safe. However, residual chlorine can be harmful to aquatic life. It can damage fish gills, affect sensitive invertebrates and harm the beneficial bacteria that maintain biological filtration. Testing free chlorine is particularly useful when: Preparing tap water for aquarium water changes. Checking water after carbon filtration. Verifying a water-treatment process. Monitoring source water used in freshwater aquariums. Checking replacement water before adding it to marine or reef aquariums. Testing water used in aquaculture and fish-holding systems. The MW10 helps identify free chlorine in a water sample so that appropriate treatment can be carried out before the water is introduced into an aquarium. Free Chlorine vs Total Chlorine – An Important Difference Understanding the difference between free chlorine and total chlorine is important when selecting a chlorine tester. Free chlorine refers to chlorine disinfectant available in its free forms, principally hypochlorous acid and hypochlorite. Combined chlorine refers to chlorine that has reacted with ammonia or other nitrogen-containing compounds. Chloramine is an important example. Total chlorine includes both free chlorine and combined chlorine. The Milwaukee MW10 measures free chlorine only. It does not measure combined chlorine or provide a total chlorine result. If your municipal water supply uses chloramine, a free-chlorine-only test may not identify all residual chlorine-based disinfectant in the water. For checking both free and combined chlorine, consider the Milwaukee MW11 Digital Total Chlorine Tester. Digital Photometer – No Guesswork with Colour Charts The MW10 uses a DPD reagent reaction and an electronic optical measurement system. When the free chlorine in the sample reacts with the DPD reagent, it produces a pink colour. The MW10 measures the intensity of this colour using a 525 nm LED light source and silicon photocell, then calculates and displays the result digitally in ppm. This removes the need to visually compare a sample against a printed colour chart. The measurement method is an adaptation of USEPA Method 330.5. How to Test Aquarium Water with the MW10 The MW10 uses a simple sample-and-reagent procedure. Fill a clean sample cuvette with 10 mL of the water being tested. Place the cuvette into the tester and close the cover. Follow the instrument's zeroing procedure. Remove the cuvette and add the contents of one Milwaukee MI526 free chlorine reagent sachet. Replace the cap and gently shake for approximately 20 seconds. Return the cuvette to the meter. Allow the instrument to complete its measurement sequence. Read the free chlorine concentration directly from the digital display in ppm. Always follow the supplied Milwaukee instruction manual for the complete testing sequence. What Should the Free Chlorine Reading Be for Aquarium Water? For aquarium water preparation, the objective is to achieve no detectable residual free chlorine before introducing replacement water into the aquarium. A reading of 0.00 ppm indicates that free chlorine is below the instrument's displayed detection resolution. It does not prove the absolute absence of every chlorine compound or other potentially harmful substance. If free chlorine is detected, review your water-treatment process and test again before using the water. Remember that a zero free-chlorine result does not rule out chloramine. If your water supply is treated with chloramine, use an appropriate total chlorine test such as the Milwaukee MW11. Suitable Aquarium Applications Freshwater aquariums Check tap water and prepared replacement water before carrying out water changes. Marine and reef aquariums Test source water and prepared replacement water as part of a wider water-quality management routine. The MW10 measures free chlorine only; it does not measure salinity, alkalinity or other reef-water parameters. Shrimp and sensitive fish systems Use free chlorine testing as an additional precaution when preparing water for sensitive aquatic livestock. Aquaculture and fish facilities Monitor incoming water and treated water used in fish-holding, hatchery and production systems. Water filtration systems Check free chlorine before and after filtration to help assess the performance of chlorine-removal systems. Reagents and Maintenance The MW10 requires Milwaukee MI526 free chlorine powder reagents for testing. The meter is supplied with six reagent sachets. Replacement reagents are available separately: MI526-25 – free chlorine powder reagents, 25 tests. Keep the glass cuvettes clean and free from fingerprints, scratches and residue. Rinse them after use and wipe the outside with a suitable lint-free cloth before placing them in the instrument. Use fresh reagents and follow the specified sample volume and reaction time to maintain reliable measurements. Technical Specifications Specification Details Model Milwaukee MW10 Measurement Free chlorine Measuring range 0.00–2.50 ppm Resolution 0.01 ppm Accuracy ±0.03 ppm ±3% of reading at 25°C Typical EMC deviation ±0.01 ppm Measurement method Adaptation of USEPA Method 330.5 Reagent method DPD powder reagent Light source LED at 525 nm Light detector Silicon photocell Calibration No calibration required Operating environment 0–50°C, maximum 95% RH non-condensing Power supply 1 × 1.5V AAA battery Auto shut-off After 2 minutes of non-use Dimensions 87.5 × 63.7 × 35.2 mm Weight Approximately 65 g Supplied With Milwaukee MW10 digital free chlorine photometer Two sample cuvettes with caps Six free chlorine powder reagent sachets 1 × 1.5V AAA battery Instruction manual A Practical Free Chlorine Tester for Aquarium Water Preparation The Milwaukee MW10 provides a convenient digital way to check free chlorine in tap water, filtered water and prepared aquarium replacement water. Its compact design, straightforward reagent-based testing and clear digital readings make it a useful addition to an aquarium water-testing setup. Check free chlorine before your next water change. The MW10 helps you monitor residual free chlorine so you can make more informed decisions about preparing water for your fish and aquatic livestock.  

    £73.56

  • Milwaukee MI56P Replacement Electrode for pH55 and pH56 2-in-1 pH / Temperature Testers Pocket Tester Milwaukee

    Milwaukee Milwaukee MI56P Replacement pH & Temperature Probe for pH55 and pH56

    The Milwaukee MI56P is a genuine replacement pH and temperature electrode designed for the Milwaukee pH55 PRO and pH56 PRO waterproof testers. If the original electrode on your Milwaukee tester has become slow to respond, produces unstable readings or has reached the end of its working life, replacing the probe can restore the instrument's measurement performance without needing to purchase a completely new tester. The MI56P combines pH and temperature-sensing functions in one replaceable electrode. When connected to a compatible Milwaukee tester, it supports automatic temperature compensation for reliable pH measurements. It is a practical replacement for aquarium keepers, aquaculture professionals and water-quality users who rely on their Milwaukee pH55 or pH56 for regular testing. Key Features Genuine Milwaukee replacement electrode – designed for the pH55 PRO and pH56 PRO testers. pH and temperature measurement – combination electrode with integrated temperature-sensing capability. Replaceable design – extends the useful life of your existing Milwaukee tester. Easy installation – slides into the tester fitting and secures with a screw-on connection. Double-junction pH electrode – designed for dependable pH measurement and reduced maintenance. Automatic temperature compensation support – works with the compatible tester's temperature-compensation function. Suitable for aquarium testing – ideal for routine pH monitoring in freshwater and marine aquarium applications. Aquaculture applications – suitable for maintaining pH measurement capability in fish-farming and aquatic systems. Why Replace Your pH Electrode? pH electrodes naturally deteriorate with use and age. Over time, you may notice: Slower response when measuring pH. Unstable or fluctuating readings. Difficulty calibrating the tester. Reduced measurement reliability. Physical damage or deterioration of the sensing element. Replacing the electrode with a compatible MI56P can help restore the performance of your Milwaukee pH55 or pH56 tester. Designed for Aquarium pH Monitoring Maintaining stable pH is an important part of aquarium management. Different fish, invertebrates and aquatic plants have different pH requirements, making regular measurement useful for monitoring water conditions. The MI56P allows existing Milwaukee pH55 and pH56 owners to continue monitoring: Freshwater aquarium pH. Marine aquarium water pH. Reef aquarium water as part of a wider testing routine. Aquaculture water conditions. Water used for aquarium water changes. pH changes during aquarium maintenance and water treatment. The probe measures pH and temperature. It does not measure other aquarium parameters such as ammonia, nitrite, nitrate, alkalinity or salinity. Compatible Milwaukee Testers The Milwaukee MI56P is designed for: Milwaukee pH55 PRO – waterproof pH and temperature tester with 0.1 pH resolution. Milwaukee pH56 PRO – waterproof pH and temperature tester with 0.01 pH resolution. The probe is not a standalone instrument. A compatible Milwaukee tester is required to display measurements. Easy Replacement The MI56P features a replaceable design that allows the electrode to be changed without replacing the complete tester. Installation involves removing the existing electrode and fitting the replacement into the tester's connection. The probe slides into the fitting and is secured by screwing the retaining section into the meter body. Follow Milwaukee's instructions when replacing the electrode and take care not to damage the connector or sealing components. Electrode Care and Maintenance Correct maintenance helps maximise electrode life and maintain reliable readings. For best results: Rinse the probe with clean water after use. Keep the pH sensing element hydrated during storage. Store the electrode using Milwaukee MA9015 storage solution. Never store the pH electrode in distilled or deionised water. Clean the electrode periodically using suitable pH electrode cleaning solution. Recalibrate the tester after replacing the electrode. Use fresh calibration solutions for accurate calibration. Recommended maintenance products: Milwaukee MA9015 – pH electrode storage solution. Milwaukee MA9016 – pH electrode cleaning solution. Milwaukee M10007B – pH 7.01 calibration solution. Milwaukee M10004B – pH 4.01 calibration solution. Technical Specifications Specification Details Model Milwaukee MI56P Product type Replacement pH and temperature electrode Compatible testers Milwaukee pH55 PRO and pH56 PRO Measurement pH and temperature sensing Electrode type Gel-filled, double-junction pH electrode Temperature compensation Supports automatic temperature compensation on compatible testers Replacement design Removable, screw-in electrode Installation Slides into tester fitting and screws into meter body Important Compatibility Information The MI56P is specifically designed for the Milwaukee pH55 PRO and pH56 PRO. It is not a universal replacement pH electrode and should not be purchased for other Milwaukee testers without checking compatibility first. Keep your Milwaukee aquarium pH tester performing reliably with the genuine MI56P replacement electrode. Replace a deteriorated probe rather than the entire instrument and continue monitoring aquarium and aquaculture water conditions.  

    £50.18

  • Milwaukee EC60 PRO Waterproof 3-in-1 EC / TDS/Temp Tester with Replaceable Probe TDS Meter Milwaukee

    Milwaukee Milwaukee EC60 PRO Waterproof EC, TDS & Temperature Tester

    The Milwaukee EC60 PRO is a professional waterproof pocket meter designed to measure electrical conductivity (EC), total dissolved solids (TDS) and temperature in water. With a wide conductivity measurement range, automatic temperature compensation and a replaceable probe, it provides a convenient way to monitor changes in dissolved mineral content. For aquarium keepers, the EC60 PRO can be used to compare source water, reverse osmosis (RO) water and prepared aquarium water, as well as monitor conductivity changes in freshwater systems. It is also suitable for hydroponics, nutrient solutions and other applications where conductivity measurements are important. Three measurements in one waterproof meter The EC60 PRO measures: Electrical conductivity (EC): 0.00–20.00 mS/cm Total dissolved solids (TDS): 0.00–10.00 ppt Temperature: 0.0–60.0°C The dual-level display shows the selected EC or TDS reading alongside the water temperature. Electrical conductivity indicates how readily water conducts electricity, which is influenced by the concentration of dissolved ions. It is a useful way to monitor changes in mineral content, although it does not identify individual minerals or contaminants. Useful for aquarium water monitoring Conductivity is a useful supporting measurement for aquarium water preparation and maintenance. The Milwaukee EC60 PRO can help you: Compare conductivity in tap water, RO water and prepared aquarium water. Monitor changes in dissolved mineral content. Check consistency when preparing water for aquarium water changes. Track conductivity changes in freshwater aquariums. Monitor water temperature alongside conductivity or TDS. Important: The EC60 PRO is not a dedicated marine aquarium salinity meter. Its maximum conductivity range is 20.00 mS/cm, which is below the conductivity of typical full-strength seawater. For routine marine aquarium salinity measurement, choose an instrument specifically designed for that application. Automatic temperature compensation Conductivity readings are affected by temperature. The EC60 PRO includes automatic temperature compensation (ATC), helping compensate for temperature-related changes during measurement. Its temperature compensation coefficient is adjustable from 0.0 to 2.4% per °C, providing flexibility for different measurement conditions. Temperature is displayed simultaneously with the EC or TDS reading, making it easier to monitor both measurements together. Replaceable measuring probe The EC60 PRO features a replaceable EC/TDS probe, helping extend the useful life of the meter without replacing the complete instrument. The compatible replacement electrode is the Milwaukee MI59P, designed for both the EC59 PRO and EC60 PRO. The probe can be replaced by unscrewing the retaining ring and fitting a new electrode. For reliable measurements, rinse the probe with clean water after use and follow the manufacturer's maintenance recommendations. Waterproof, practical design Designed for use around water, the EC60 PRO features an IP65-rated waterproof housing and a floating casing. Additional features include: Automatic one-point calibration. Automatic temperature compensation. Adjustable temperature compensation coefficient. Dual-level LCD display. Measurement stability indicator. Battery level indicator. Hold function. Automatic shut-off after approximately eight minutes of inactivity. Temperature display in °C or °F. Replaceable measuring probe. Technical specifications Specification EC60 PRO EC range 0.00–20.00 mS/cm EC resolution 0.01 mS/cm EC accuracy ±2% of full scale TDS range 0.00–10.00 ppt TDS resolution 0.01 ppt TDS accuracy ±2% of full scale Temperature range 0.0–60.0°C / 32.0–140.0°F Temperature resolution 0.1°C / 0.1°F Temperature accuracy ±0.5°C / ±1°F Calibration Automatic, one point Calibration standard 12.88 mS/cm Temperature compensation Automatic, adjustable β = 0.0–2.4%/°C Replaceable probe Milwaukee MI59P Operating environment 0–50°C Waterproof rating IP65 Batteries 4 × 1.5V LR44 / A76 alkaline Battery life Approximately 100 hours Auto shut-off After approximately 8 minutes Understanding EC and TDS measurements EC measures the electrical conductivity of water and is expressed in µS/cm or mS/cm. TDS is an estimated value derived from conductivity using a conversion factor. Different conversion scales, such as 0.5 and 0.7, can produce different TDS readings from the same water sample. For this reason, TDS readings from different meters may not be directly comparable unless the same conversion scale is being used. For consistent aquarium monitoring, EC is often the more useful measurement to record and compare. Supplied with Milwaukee EC60 PRO meter. Replaceable EC/TDS probe. Protective cap. 12.88 mS/cm calibration solution sachet. Four batteries. Instructions. Recommended accessories Milwaukee MI59P replacement probe – replacement EC/TDS electrode compatible with the EC59 PRO and EC60 PRO. Milwaukee MA9060 calibration solution – 12.88 mS/cm conductivity calibration solution in a 230 ml bottle. Milwaukee M10030B calibration sachets – 12.88 mS/cm calibration solution in convenient individual sachets. Milwaukee MA9016 cleaning solution – helps maintain the measuring probe. The Milwaukee EC60 PRO is a versatile choice for users who need a waterproof conductivity and TDS tester with a wider measurement range, replaceable probe and simultaneous temperature display.

    £69.90

  • Last stock! Milwaukee MA73600 Replacement Electrode for PH51 & PH54 Testers Handheld Spares Milwaukee

    Milwaukee Milwaukee MA73600 Replacement pH Electrode for pH51 & pH54

    The Milwaukee MA73600 is a genuine replacement pH electrode designed for the Milwaukee pH51 and pH54 waterproof pH testers. Over time, pH electrodes can deteriorate through normal use, contamination, drying out or inadequate maintenance. Replacing a worn or damaged electrode helps keep your compatible Milwaukee tester in service and supports reliable pH measurement. For aquarium keepers, water-quality professionals and other users who regularly monitor pH, the MA73600 provides a practical replacement for the original measuring electrode. Compatible with Milwaukee pH51 and pH54 The MA73600 is designed for use with: Milwaukee pH51 waterproof pH tester. Milwaukee pH54 waterproof pH tester. It is a replacement electrode for these specific instruments. Please check your meter model before ordering to ensure compatibility. Suitable for aquarium pH monitoring Maintaining a reliable pH tester is important when monitoring aquarium water quality. The MA73600 replacement electrode helps keep a compatible Milwaukee tester operational for routine pH checks, including: Freshwater aquarium monitoring. Checking pH in prepared aquarium water. Monitoring pH changes during routine maintenance. Testing water used for fishkeeping and aquatic systems. The electrode measures pH when connected to a compatible meter. It does not independently display or process pH readings. Why replace a pH electrode? A pH electrode is a consumable measuring component. Its performance can gradually decline, particularly if it is allowed to dry out, becomes contaminated or is not maintained correctly. Common reasons for replacement include: Slow response when taking measurements. Unstable or inconsistent readings. An electrode that has become damaged. Reduced performance despite correct cleaning and calibration. An electrode that has reached the end of its useful service life. Replacing the electrode can help restore the performance of a compatible tester, although the condition of the meter itself and correct calibration also affect measurement results. Electrode care and maintenance Correct storage and regular maintenance help extend the working life of a pH electrode. For best results: Keep the electrode hydrated using a suitable pH electrode storage solution. Do not store the electrode in distilled or deionised water. Rinse the electrode with suitable rinse solution or clean water between samples. Use an appropriate electrode cleaning solution when contamination is suspected. Calibrate the pH meter using fresh, suitable buffer solutions. Follow Milwaukee's instructions for electrode replacement and conditioning. Technical compatibility Specification Details Product code MA73600 Product type Replacement pH electrode Compatible instruments Milwaukee pH51 and pH54 Measurement parameter pH Installation Replacement electrode for compatible tester Application Water-quality and pH measurement Recommended accessories For reliable pH measurements and good electrode maintenance, consider: Milwaukee MA9015 storage solution – helps keep the pH electrode properly hydrated during storage. Milwaukee MA9016 cleaning solution – for cleaning the electrode when contamination affects performance. Milwaukee M10004B pH 4.01 buffer solution – calibration buffer for acidic-range measurements. Milwaukee M10007B pH 7.01 buffer solution – calibration buffer for neutral-range measurements. Milwaukee M10010B pH 10.01 buffer solution – calibration buffer for alkaline-range measurements. Milwaukee M10000B electrode rinse solution – for rinsing the electrode between measurements. The Milwaukee MA73600 is the correct replacement electrode for users who want to maintain their existing Milwaukee pH51 or pH54 tester rather than replace the complete instrument.

    £30.31

  • Last stock! Milwaukee TH300 Digital Thermometer Thermometer Milwaukee

    Milwaukee Milwaukee TH300 Digital Aquarium & Water Thermometer

    The Milwaukee TH300 is a compact digital thermometer designed for accurate and convenient temperature measurement in water and other applications. Supplied with a stainless-steel probe connected to the meter by a flexible 1-metre cable, it makes checking temperatures in difficult-to-reach areas straightforward. For aquarium keepers, the TH300 provides a convenient way to check aquarium water temperature, compare replacement water before water changes and monitor temperatures in different tanks. With a wide measurement range of -50.0 to 150.0°C, a clear digital display and 0.1°C resolution, the TH300 is also suitable for brewing, winemaking, food preparation, educational experiments and general laboratory use. Ideal for aquarium temperature checks Temperature is an important water-quality parameter in aquarium keeping. Monitoring it helps ensure that aquarium water and replacement water are within the intended temperature range for the livestock being kept. The Milwaukee TH300 can be used to: Check the temperature of freshwater aquarium water. Compare aquarium temperature with replacement water before a water change. Check water temperature in breeding and quarantine tanks. Monitor the temperature of prepared water. Take measurements in containers and other hard-to-reach locations. The 1-metre cable allows the stainless-steel probe to reach into a tank or sample while the digital display remains conveniently positioned outside. Stainless-steel probe with 1-metre cable The TH300 is supplied with a general-purpose stainless-steel temperature probe connected to the meter by a flexible 1-metre cable. Simply place the probe in the sample being measured and allow the reading to stabilise. The stainless-steel probe is durable, easy to clean and suitable for repeated temperature measurements in water and other samples. Keep the meter housing and electrical connections dry. The TH300 is a portable thermometer, not a waterproof aquarium controller designed for permanent installation. Wide temperature measurement range The Milwaukee TH300 measures temperatures from -50.0 to 150.0°C, making it suitable for a wide range of applications. Its 0.1°C resolution allows users to see temperature changes in small increments. The specified accuracy is ±0.5°C between -20°C and 90°C. Clear digital display and simple operation The TH300 features a large LCD display designed to make temperature readings easy to see. Its straightforward operation makes it suitable for aquarium keepers, laboratories, brewing applications and general-purpose temperature checks. The meter is supplied with a battery and has an approximate battery life of one year under normal use. Technical specifications Specification Milwaukee TH300 Measurement range -50.0 to 150.0°C Resolution 0.1°C Accuracy ±0.5°C from -20 to 90°C Typical EMC deviation ±0.3°C Probe material Stainless steel Probe cable length 1 metre Display Digital LCD Battery 1 × 1.5V AAA Approximate battery life 1 year Operating environment 0 to 50°C Maximum relative humidity 95% Calibration check Not available Power switch No separate ON/OFF switch Supplied with Milwaukee TH300 digital thermometer. Stainless-steel temperature probe. 1-metre probe cable. Battery. Instruction manual. Suitable for more than aquarium use Although particularly useful for aquarium temperature checks, the TH300 is a versatile general-purpose thermometer. Other applications include: Brewing and winemaking. Food and beverage preparation. Educational experiments. Laboratory temperature checks. General liquid temperature measurement. The Milwaukee TH300 is a practical choice for aquarium keepers and other users who need a compact digital thermometer with a remote stainless-steel probe and a wide temperature measurement range.

    £45.04

  • Milwaukee MW401 PRO Low Range Total Dissolved Solids Meter Handheld Meter Milwaukee

    Milwaukee Milwaukee MW401 PRO Low-Range TDS Meter

    The Milwaukee MW401 PRO is a portable low-range total dissolved solids (TDS) meter designed to measure dissolved-solids levels in water. With a measurement range of 0–1,999 ppm, 1 ppm resolution and automatic temperature compensation, it provides a convenient way to monitor changes in water composition. For aquarium keepers, the MW401 PRO is useful for comparing tap water, reverse osmosis (RO) water and prepared aquarium water, as well as tracking changes in dissolved-solids levels over time. The meter is supplied with a separate SE510 conductivity probe, a 1-metre cable and calibration solution, making it suitable for aquarium, aquaculture, water conditioning and laboratory applications. Low-range TDS measurement The MW401 PRO measures total dissolved solids from 0 to 1,999 mg/L (ppm), with a resolution of 1 ppm. TDS is an estimate of the concentration of dissolved substances in water. It is calculated from electrical conductivity using a conversion factor. The MW401 PRO uses a fixed TDS conversion factor of 0.5. This provides consistent readings when monitoring water samples, provided measurements are taken under comparable conditions. Useful for aquarium water monitoring TDS measurements can provide useful information about changes in dissolved mineral content in aquarium water. The MW401 PRO can help aquarium keepers: Compare TDS levels in tap water and reverse osmosis water. Check prepared water before aquarium water changes. Monitor changes in dissolved-solids levels over time. Track water consistency in freshwater aquariums. Check water used for fishkeeping and aquaculture. Monitor changes in water conditioning and treatment processes. TDS is a supporting water-quality measurement rather than a complete assessment of aquarium water quality. A TDS reading cannot identify individual minerals, nutrients or contaminants, so it should be considered alongside other relevant water tests. Automatic temperature compensation Temperature affects the electrical conductivity of water, which is used to calculate the TDS reading. The MW401 PRO incorporates automatic temperature compensation (ATC) from 5 to 50°C, helping compensate for temperature-related changes during measurement. This supports more consistent readings when testing samples at different temperatures within the instrument's compensation range. Separate SE510 probe with 1-metre cable The MW401 PRO is supplied with a separate SE510 conductivity/TDS probe connected to the meter by a 1-metre cable. This arrangement allows the probe to be immersed in the water sample while the display remains conveniently positioned outside the container. The probe is designed for conductivity measurement, from which the instrument calculates the TDS value. Simple calibration The MW401 PRO features manual calibration using the adjustment control on the front of the meter. It is calibrated using a 1382 ppm TDS standard, and a starter calibration solution is supplied with the instrument. For consistent results, recalibrate regularly and whenever the probe or battery is changed. Use fresh calibration solution and follow the manufacturer's instructions. Portable design and straightforward operation The MW401 PRO is designed for practical water testing in the laboratory, aquarium room, water-treatment environment or field. Features include: Large, easy-to-read digital display. Portable handheld meter. Separate probe with 1-metre cable. Automatic temperature compensation. Manual calibration adjustment. Approximately 300 hours of battery operation. 9V battery supplied. Technical specifications Specification Milwaukee MW401 PRO Measurement parameter Total dissolved solids (TDS) TDS range 0–1,999 mg/L (ppm) TDS resolution 1 mg/L (ppm) Accuracy at 25°C ±2% of full scale TDS conversion factor 0.5 Temperature compensation Automatic Compensation range 5–50°C Probe Milwaukee SE510 conductivity/TDS probe Probe cable 1 metre Calibration Manual Calibration standard 1382 ppm Operating environment 0–50°C Maximum relative humidity 95% Battery 1 × 9V alkaline Approximate battery life 300 hours Meter dimensions 143 × 80 × 32 mm Meter weight Approximately 220 g including battery Supplied with Milwaukee MW401 PRO TDS meter. SE510 conductivity/TDS probe. 1-metre probe cable. 1382 ppm calibration solution sachet. Calibration adjustment screwdriver. 9V alkaline battery. Instructions. Recommended accessories Milwaukee M10032B calibration solution – 1382 ppm TDS calibration solution supplied in individual 20 ml sachets. Milwaukee MA9062 calibration solution – 1382 ppm TDS calibration solution in a 230 ml bottle. The Milwaukee MW401 PRO is a practical choice for aquarium keepers, aquaculture operators and water-quality professionals who need a portable low-range TDS meter with automatic temperature compensation and a separate measuring probe.

    £138.47

  • Milwaukee MW301 PRO Conductivity Meter Handheld Meter Milwaukee

    Milwaukee Milwaukee MW301 PRO Conductivity (EC) Meter

    The Milwaukee MW301 PRO is a portable conductivity meter designed to measure electrical conductivity (EC) in water and other liquid samples. With a low-range measurement capability of up to 1,999 µS/cm, 1 µS/cm resolution and automatic temperature compensation, it provides a practical way to monitor changes in dissolved ionic content. For aquarium keepers, the MW301 PRO is useful for comparing tap water, reverse osmosis (RO) water and prepared aquarium water, as well as monitoring conductivity changes in freshwater systems. Supplied with a separate SE510 conductivity probe, 1-metre cable and calibration solution, the MW301 PRO is also suitable for hydroponics, agriculture, water conditioning, education and laboratory applications. Low-range conductivity measurement The MW301 PRO measures electrical conductivity from 0 to 1,999 µS/cm, with a resolution of 1 µS/cm. Conductivity indicates how readily water conducts electricity. It is influenced by the concentration of dissolved ions, including minerals and salts. Monitoring EC can help identify changes in water composition and consistency, making it a useful supporting measurement for aquarium water preparation and general water-quality monitoring. Useful for freshwater aquarium monitoring Conductivity is an important supporting measurement for understanding changes in freshwater chemistry. The MW301 PRO can help aquarium keepers: Compare conductivity in tap water and reverse osmosis water. Check prepared water before aquarium water changes. Monitor changes in dissolved ionic content over time. Compare conductivity between different freshwater aquariums. Check the consistency of water used for fishkeeping and aquaculture. Monitor changes in water conditioning and treatment processes. Conductivity does not identify individual minerals or contaminants, and an EC reading alone cannot establish whether aquarium water is suitable for a particular species. Automatic temperature compensation Water conductivity changes with temperature. The MW301 PRO incorporates automatic temperature compensation (ATC) from 5 to 50°C, helping compensate for temperature-related variations during measurement. This supports more consistent readings when comparing water samples taken at different temperatures within the compensation range. Separate SE510 conductivity probe with 1-metre cable The MW301 PRO is supplied with a separate Milwaukee SE510 conductivity probe connected to the meter by a 1-metre cable. This allows the probe to be immersed in a sample while the digital display remains outside the container. The probe is replaceable, helping extend the useful life of the meter without replacing the complete instrument. For reliable measurements, rinse the probe after use and follow the manufacturer's cleaning and maintenance instructions. Simple manual calibration The MW301 PRO uses manual one-point calibration with a 1413 µS/cm conductivity standard. The instrument is supplied with a calibration solution sachet and a small screwdriver for adjusting the calibration control. For consistent results, recalibrate regularly and whenever the probe or battery is changed. Use fresh calibration solution and follow Milwaukee's calibration procedure. Portable design for practical water testing The MW301 PRO features a compact handheld design and a large digital display for straightforward conductivity measurement. Additional features include: 0–1,999 µS/cm conductivity range. 1 µS/cm resolution. Automatic temperature compensation. Manual calibration adjustment. Separate replaceable conductivity probe. 1-metre probe cable. Approximately 300 hours of battery operation. 9V alkaline battery supplied. Technical specifications Specification Milwaukee MW301 PRO Measurement parameter Electrical conductivity (EC) Conductivity range 0–1,999 µS/cm Conductivity resolution 1 µS/cm Accuracy at 25°C ±2% of full scale Calibration Manual, one point Calibration standard 1413 µS/cm Temperature compensation Automatic Compensation range 5–50°C Probe Milwaukee SE510 conductivity probe Probe cable 1 metre Operating environment 0–50°C Maximum relative humidity 95% Battery 1 × 9V alkaline Approximate battery life 300 hours Meter dimensions 143 × 80 × 32 mm Meter weight Approximately 220 g including battery Supplied with Milwaukee MW301 PRO conductivity meter. SE510 conductivity probe. 1-metre probe cable. 20 ml sachet of 1413 µS/cm calibration solution. Calibration adjustment screwdriver. 9V alkaline battery. Instructions. Recommended accessories Milwaukee SE510 replacement probe – replacement conductivity electrode with DIN connector and 1-metre cable. Milwaukee M10031B calibration solution – 1413 µS/cm conductivity calibration solution in individual 20 ml sachets. Milwaukee MA9061 calibration solution – 1413 µS/cm conductivity calibration solution in a 230 ml bottle. Milwaukee MA950 wall mounting kit – optional mounting accessory for the meter. The Milwaukee MW301 PRO is a practical choice for aquarium keepers, aquaculture operators and water-quality professionals who need a portable, low-range conductivity meter with automatic temperature compensation and a replaceable measuring probe.

    £138.47

  • Last stock! Milwaukee MW14 Digital Iron Tester Pocket Tester Milwaukee

    Milwaukee Milwaukee MW14 Digital Iron Photometer – 0–5.00 ppm

    The Milwaukee MW14 is a compact digital iron photometer designed to measure iron concentrations in natural and treated water. With a measurement range of 0.00 to 5.00 ppm, 0.01 ppm resolution and digital results, it provides a convenient alternative to visually comparing traditional colour-based iron test kits. For aquarium keepers, the MW14 can help monitor iron concentrations in freshwater systems, including planted aquariums where iron is an important plant nutrient. It is also suitable for aquaculture, water conditioning, laboratory and educational applications. Using an adaptation of the EPA Phenanthroline Method 315B, the MW14 measures the colour reaction produced when iron reacts with the supplied reagent. Its internal photometer evaluates the colour intensity and displays the calculated iron concentration on the digital screen. Digital iron measurement for aquarium water Iron is an important trace element in aquatic systems. It is particularly relevant to planted aquariums, where iron contributes to healthy plant growth and is commonly supplied through aquarium fertilisers. The Milwaukee MW14 can help aquarium keepers: Monitor iron concentrations in freshwater aquariums. Check iron levels when managing planted aquarium fertilisation. Compare iron concentrations before and after dosing. Monitor iron in prepared aquarium water. Support routine water-quality testing in aquaculture systems. Regular testing can help identify changes in iron concentration and provide additional information when managing aquarium fertilisation. Important: The MW14 is a high-range iron photometer. Its accuracy specification should be considered when measuring very low iron concentrations, particularly in planted aquariums where trace-level measurements may be required. High-range iron measurement: 0.00–5.00 ppm The MW14 measures iron concentrations from 0.00 to 5.00 ppm, with a resolution of 0.01 ppm. Its stated accuracy at 25°C is ±0.04 ppm ±2% of the reading. The digital display provides a numerical result, avoiding the need to visually match a sample against a colour chart. Photometric measurement using the Phenanthroline method The MW14 uses an adaptation of the EPA Phenanthroline Method 315B for natural and treated waters. The testing process uses a dedicated iron reagent that reacts with iron in the sample, producing an orange colour. The instrument measures the intensity of this colour using an LED light source and silicon photocell. The photometer then calculates and displays the iron concentration in ppm. This provides a more objective way to interpret the colour reaction than manually comparing a sample against a printed colour scale. Simple testing procedure The MW14 is designed to make iron testing straightforward. The general measurement procedure is: Fill the supplied cuvette with 10 ml of the water sample. Place the cuvette into the instrument and perform the zeroing procedure. Remove the cuvette and add one sachet of the supplied iron reagent. Replace the cap and gently shake for two minutes until the reagent has dissolved. Return the cuvette to the instrument. Allow the specified reaction time of two minutes and thirty seconds. Read the iron concentration directly from the digital display. Always follow the supplied Milwaukee instructions and use the correct reagent for the MW14. No calibration required The MW14 is factory calibrated and does not require routine user calibration. Testing is carried out using the supplied reagent sachets and glass cuvettes. Keeping the cuvettes clean and free from fingerprints, scratches and water droplets is important for reliable photometric measurements. Compact and portable design The MW14 is a small handheld photometer suitable for use in aquarium rooms, laboratories, aquaculture facilities and water-treatment environments. Features include: Digital LCD display. Measurement range of 0.00–5.00 ppm. 0.01 ppm resolution. Accuracy of ±0.04 ppm ±2% of reading at 25°C. LED light source at 525 nm. Silicon photocell detector. No user calibration required. Automatic shut-off. Powered by one AAA battery. Technical specifications Specification Milwaukee MW14 Measurement parameter Iron (Fe) Measurement range 0.00–5.00 ppm Resolution 0.01 ppm Accuracy at 25°C ±0.04 ppm ±2% of reading Typical EMC deviation ±0.01 ppm Measurement method Adaptation of EPA Phenanthroline Method 315B Light source LED at 525 nm Light detector Silicon photocell Sample volume 10 ml Calibration Factory calibrated; no user calibration required Operating temperature 0–50°C Maximum relative humidity 95%, non-condensing Battery 1 × 1.5V AAA Auto shut-off After 3 minutes of inactivity and 2 minutes after a reading Dimensions 87.5 × 63.7 × 35.2 mm Weight Approximately 65 g Supplied with Milwaukee MW14 digital iron photometer. Two glass sample cuvettes with caps. Six iron reagent sachets. One 1.5V AAA battery. Instruction manual. Recommended accessories and consumables Milwaukee MI528-25 iron reagent – replacement iron reagent set containing 25 sachets for the MW14. Milwaukee MI0011 glass cuvettes – replacement sample cuvettes. Milwaukee MI0013 cuvette stoppers – replacement stoppers for compatible glass cuvettes. Milwaukee cuvette cleaning tissues – useful for keeping optical sample containers clean. The Milwaukee MW14 is a practical choice for aquarium keepers, aquaculture operators and water-quality professionals who want a compact digital instrument for measuring iron concentrations in natural and treated water.

    £73.56

  • Last stock! Milwaukee MW13 digital iodine photometer for measuring iodine concentration in water

    Milwaukee Milwaukee MW13 Digital Iodine Photometer – Water Tester

    The Milwaukee MW13 Digital Iodine Tester is a compact handheld photometer designed to measure iodine concentration in water. With a measurement range of 0.0 to 12.5 ppm, it provides a straightforward way to monitor iodine levels in water-treatment, aquaculture, laboratory and other specialist water-testing applications. Instead of relying on visual colour comparison with test strips, the MW13 uses a reagent-based photometric method to produce a digital iodine reading. This makes results easier to read and record, helping users carry out repeatable water-quality checks. Digital iodine testing for water quality monitoring Iodine is used in certain water-treatment and disinfection applications, including specialist aquaculture and fish-farming processes. Where iodine levels need to be monitored, the MW13 provides a dedicated measurement instrument. The tester uses an adaptation of the DPD method described in the Standard Methods for the Examination of Water and Wastewater, 18th edition. When the iodine reagent is added to the water sample, it produces a pink colour. The MW13 measures the colour intensity using an optical system and calculates the iodine concentration. The result is displayed directly in ppm, without the need to judge the colour by eye. Key features Dedicated iodine measurement: Designed specifically for iodine testing in water. Measurement range: 0.0–12.5 ppm. Resolution: 0.1 ppm. Accuracy: ±0.1 ppm ±5% of the reading at 25°C. Digital display: Clear numerical results instead of subjective visual colour matching. Reagent-based method: Uses Milwaukee iodine powder reagents. Simple operation: Straightforward sample preparation and measurement process. No manual calibration required: The instrument uses a sample-zeroing step before the reagent is added. Compact and portable: Suitable for testing at the point of use. Automatic shut-off: Helps conserve battery power. How the Milwaukee MW13 works The MW13 uses a photometric measurement method. The iodine reagent reacts with the sample to produce a pink colour, and the instrument measures the intensity of that colour to calculate the iodine concentration. The basic testing procedure is: Fill a clean cuvette with 10 mL of the water sample. Place the cuvette in the tester and carry out the initial zeroing step. Remove the cuvette and add one packet of Milwaukee MI527 iodine reagent. Replace the cap and shake gently for approximately 20 seconds until the powder dissolves. Return the cuvette to the instrument. Allow the reaction time of 2 minutes and 30 seconds. Read the iodine concentration displayed in ppm. Always follow the supplied instruction manual and use the specified reagent. Technical specifications Specification Detail Manufacturer Milwaukee Instruments Model MW13 Measurement parameter Iodine Measurement range 0.0–12.5 ppm Resolution 0.1 ppm Accuracy ±0.1 ppm ±5% of reading at 25°C Typical EMC deviation ±0.1 ppm Light source LED, 525 nm Light detector Silicon photocell Measurement method Adaptation of the DPD method Sample volume 10 mL Operating temperature 0–50°C Maximum relative humidity 95%, non-condensing Battery 1 × 1.5V AAA Automatic shut-off After 2 minutes of non-use Dimensions 87.5 × 63.7 × 35.2 mm Weight Approximately 65 g What is included? The Milwaukee MW13 is supplied with: MW13 digital iodine photometer 2 sample cuvettes with caps 6 iodine powder reagent sachets 1 × 1.5V AAA battery Instruction manual Replacement reagents and accessories For continued testing, the MW13 requires the correct iodine reagent. MI527-25 iodine reagent: Replacement pack containing 25 powder reagent sachets. MI0011 glass cuvettes: Replacement sample cuvettes. MI0013 cuvette stoppers: Replacement stoppers for compatible cuvettes. Use only the specified reagent and compatible cuvettes to maintain reliable measurement performance. Is the Milwaukee MW13 suitable for aquarium and aquaculture water testing? The MW13 can be useful in specialist aquarium and aquaculture applications where iodine concentration is a specific parameter of interest, particularly where iodine is used as part of a controlled water-treatment process. It is important to distinguish iodine testing from routine aquarium water testing. The MW13 is not designed to measure iodide, iodate or every form of iodine independently, nor does it provide a general assessment of aquarium water quality. Its measurement is based on the specified reagent method. For routine aquarium monitoring, other parameters such as pH, ammonia, nitrite, nitrate, phosphate and chlorine may also need to be checked using appropriate dedicated tests. Why choose the Milwaukee MW13? The MW13 offers a convenient digital alternative to visual iodine test methods. Its dedicated measurement range, simple reagent procedure and clear digital display make it a practical option for users who need to monitor iodine in water-treatment, aquaculture or laboratory applications. Available from GroAqua – water testing equipment and water-quality measurement solutions.

    £73.56

  • Last stock! Milwaukee MW12 digital phosphate photometer for aquarium and water quality testing

    Milwaukee Milwaukee MW12 Digital Phosphate Photometer – Water Tester

    The Milwaukee MW12 Digital Phosphate Tester is a compact, handheld photometer designed to measure phosphate concentration in water. With a low-range measurement capability of 0.00 to 2.50 ppm, it provides a convenient way to monitor phosphate levels in aquariums, aquaculture systems, fish farms, water-treatment applications and laboratories. Using a reagent-based photometric method, the MW12 produces a digital phosphate reading instead of relying on visual colour comparison. Its simple testing procedure and clear LCD display make it a practical instrument for regular water-quality checks. Digital phosphate testing for water quality monitoring Phosphate is an important water-quality parameter in both freshwater and marine environments. In aquariums, phosphate levels are commonly monitored as part of a wider water-quality management routine. Elevated phosphate can contribute to unwanted algae growth, while reef aquarium keepers and planted aquarium enthusiasts may monitor phosphate to help manage nutrient balance. In aquaculture and fish-farming systems, phosphate testing can contribute to wider water-quality assessment and monitoring. It can also be useful in water treatment, laboratory and educational settings where phosphate concentration needs to be measured. The Milwaukee MW12 provides a digital measurement from a prepared water sample, helping users obtain consistent readings without estimating colour changes by eye. Key features Dedicated phosphate measurement: Designed specifically for phosphate testing in water. Low-range measurement: Measures from 0.00 to 2.50 ppm. Fine display resolution: 0.01 ppm. Specified accuracy: ±0.04 ppm ±4% of the reading at 25°C. Digital LCD display: Clear numerical results without visual colour matching. Photometric measurement: Uses a 525 nm LED light source and silicon photocell detector. Reagent-based testing: Uses Milwaukee MI512 phosphate powder reagents. Simple operation: Sample zeroing, reagent addition and timed measurement. No manual calibration required: The instrument uses a zeroing procedure before the reagent is added. Portable design: Compact and lightweight for testing at the point of use. How does the Milwaukee MW12 work? The MW12 uses an adaptation of the ascorbic acid method described in the 20th edition of the Standard Methods for the Examination of Water and Wastewater. When the phosphate reagent is added to the water sample, a chemical reaction produces a blue colour. The photometer measures the intensity of this colour using its optical system and calculates the phosphate concentration. The result is displayed directly in ppm. How to use the Milwaukee MW12 The testing process is straightforward: Fill a clean sample cuvette with 10 mL of untreated water and fit the cap. Place the cuvette into the tester and close the instrument cover. Switch on the MW12 and follow the display prompts to zero the instrument using the untreated sample. Remove the cuvette and add the contents of one MI512 phosphate reagent sachet. Replace the cap and shake gently for approximately 2 minutes until the powder has dissolved. Return the cuvette to the tester. Allow the reaction to develop for 3 minutes, following the instrument's countdown procedure. The MW12 displays the phosphate concentration directly in ppm. Use the supplied instructions and the specified Milwaukee reagent for reliable testing. Technical specifications Specification Detail Manufacturer Milwaukee Instruments Model MW12 Measurement parameter Phosphate Measurement range 0.00–2.50 ppm Resolution 0.01 ppm Accuracy ±0.04 ppm ±4% of reading at 25°C Typical EMC deviation ±0.01 ppm Measurement method Adaptation of the ascorbic acid method Light source LED, 525 nm Light detector Silicon photocell Sample volume 10 mL Operating temperature 0–50°C Maximum relative humidity 95%, non-condensing Battery 1 × 1.5V AAA Automatic shut-off 10 minutes of non-use; 2 minutes after a reading Dimensions 81.5 × 61 × 37.5 mm Weight 64 g What is included? The Milwaukee MW12 is supplied with: MW12 digital phosphate photometer 2 sample cuvettes with caps 6 phosphate low-range powder reagent sachets 1 × 1.5V AAA battery Instruction manual Replacement reagents and accessories The MW12 requires phosphate reagent sachets for testing. For ongoing use, replacement consumables are available: MI512-25 phosphate reagent: Pack of 25 powder reagent sachets. MI0011 glass cuvettes: Replacement sample cuvettes. MI0013 cuvette stoppers: Replacement stoppers for compatible cuvettes. Using the correct reagent and keeping the cuvettes clean and free from scratches helps support consistent measurements. Is the Milwaukee MW12 suitable for aquarium water testing? Yes. The MW12 is particularly useful for aquarium keepers who want to monitor phosphate levels as part of their water-quality routine. Phosphate is relevant to both freshwater and marine aquariums. It is often monitored in planted aquariums, reef systems and other environments where nutrient balance is important. The MW12's 0.00–2.50 ppm range makes it suitable for measuring phosphate across a range of aquarium and water-treatment applications. However, users should consider its specified accuracy when interpreting very low phosphate readings. Although the display resolves to 0.01 ppm, the stated accuracy is ±0.04 ppm plus 4% of the reading at 25°C. It should therefore not be treated as an ultra-low-range reference instrument. For a more complete picture of aquarium water quality, phosphate should be considered alongside other parameters such as pH, ammonia, nitrite, nitrate, alkalinity and conductivity, using suitable dedicated instruments or tests. Why choose the Milwaukee MW12? The Milwaukee MW12 offers a convenient way to measure phosphate in water without relying on visual colour charts. Its compact design, simple reagent procedure and digital readout make it suitable for regular water-quality monitoring in aquariums, aquaculture, laboratories and water-treatment applications. Available from GroAqua – water testing equipment and water-quality monitoring solutions.

    £73.56

Accurate water testing is an important part of maintaining water quality in aquariums, hydroponic systems, aquaculture facilities and water treatment applications. Measuring parameters such as pH, electrical conductivity, total dissolved solids and dissolved oxygen helps you understand water conditions and make informed adjustments.

At GroAqua, we stock Milwaukee Instruments digital water testers, handheld meters and accessories for a variety of testing requirements. The collection includes pH meters, EC and TDS testers, dissolved oxygen meters, temperature testers and specialist photometers.

Whether you are monitoring nutrient solutions in a hydroponic system, checking aquarium water quality or measuring dissolved oxygen in an aquaculture environment, Milwaukee offers a range of instruments to support routine water testing.

Milwaukee pH Meters and Digital pH Testers

pH measures how acidic or alkaline a water-based solution is. It is one of the most important parameters to monitor in aquariums, hydroponics, aquaculture and many water treatment applications.

A digital pH meter provides a numerical reading, allowing you to monitor changes and compare results against your required operating range.

Milwaukee offers several types of pH testing equipment, including compact pocket testers and professional handheld meters.

Depending on the model, features may include:

  • Digital LCD displays for straightforward reading.

  • Manual or automatic calibration.

  • One-point or two-point calibration options.

  • Replaceable pH electrodes on selected models.

  • Automatic temperature compensation on compatible instruments.

  • Waterproof construction on specified pocket testers.

  • Portable designs for field and routine testing.

Models such as the Milwaukee pH600AQ, pH51, pH55 PRO and MW101 PRO offer different features and measurement capabilities.

When selecting a pH tester, consider the required measurement range, accuracy, calibration method, electrode type and intended application.

Milwaukee EC Meters and Conductivity Testers

Electrical conductivity (EC) measures how readily a solution conducts electricity. It provides an indication of the concentration of dissolved ions in water and is widely used to monitor nutrient solutions in hydroponics and horticulture.

EC measurement is also useful in aquaculture, water treatment and other applications where dissolved ionic content needs to be monitored.

Milwaukee EC testers are available in compact pocket formats and more advanced handheld instruments.

Depending on the model, features may include:

  • Direct conductivity measurement in microsiemens (µS/cm) or millisiemens (mS/cm).

  • Automatic temperature compensation.

  • Replaceable electrodes on selected models.

  • Calibration functions.

  • Portable digital displays.

The Milwaukee CD601 and EC59 PRO are examples of instruments designed to measure electrical conductivity.

For hydroponic growers, regular EC testing helps monitor nutrient solution strength and identify changes that may require attention.

Milwaukee TDS Meters

Total dissolved solids (TDS) refers to the concentration of dissolved substances in water, commonly expressed in parts per million (ppm).

TDS meters are frequently used in hydroponics, aquariums and water treatment to monitor changes in dissolved material.

Milwaukee TDS testers include compact digital instruments such as the CD600, designed for convenient measurement.

TDS readings are often calculated from electrical conductivity using a conversion factor. Different meters and applications may use different conversion scales, so readings from different instruments may not always be directly comparable.

For more precise nutrient management, it is important to understand whether your instrument displays EC, TDS or both, and which conversion scale it uses.

Combined pH, EC and TDS Meters

Combination meters allow users to measure multiple water parameters using one instrument. These can be particularly useful for hydroponic growers and aquarium owners who regularly monitor several aspects of water quality.

Milwaukee combination testers include models such as the MW801 PRO and MW803 MAX.

Depending on the model, these instruments can measure:

  • pH.

  • Electrical conductivity (EC).

  • Total dissolved solids (TDS).

  • Temperature.

Some combination meters feature automatic temperature compensation, replaceable probes and automatic calibration.

Using a multi-parameter meter can simplify routine testing and reduce the need to carry several separate instruments.

When choosing a combination tester, check the measurement ranges, accuracy specifications, probe configuration and calibration requirements for each parameter.

Milwaukee Dissolved Oxygen Meters

Dissolved oxygen (DO) is the amount of oxygen present in water. It is a particularly important parameter in fish farming, aquaculture, ponds and aquatic research.

Fish and other aquatic organisms depend on sufficient dissolved oxygen, while biological processes in aquatic systems can also be affected by oxygen availability.

A dissolved oxygen meter provides a numerical measurement, helping users monitor oxygen conditions and identify changes.

The Milwaukee MW600 PRO is a portable dissolved oxygen meter designed for applications including aquaculture, fish farming, ponds and field testing.

Its features include a digital display, a polarographic oxygen probe and a replaceable membrane system.

When selecting a dissolved oxygen meter, consider:

  • Measurement range and resolution.

  • Accuracy specifications.

  • Probe type and cable length.

  • Calibration procedure.

  • Membrane and electrolyte replacement requirements.

  • Temperature compensation requirements.

Regular probe maintenance and correct calibration are important for obtaining reliable dissolved oxygen measurements.

Milwaukee Photometers and Water Testing Instruments

Photometers use light measurement to determine the concentration of particular substances in a water sample. They provide a digital alternative to visual colour comparison methods used in some water testing procedures.

Milwaukee offers specialist photometers for selected water quality parameters, including chlorine and other substances.

For example, the MW11 total chlorine photometer uses a reagent-based testing method to produce a digital measurement.

Photometers are useful in applications where a specific parameter needs to be measured rather than relying on a general conductivity or pH reading.

Always use the correct reagent for the instrument and follow the manufacturer's sample preparation and testing instructions.

Milwaukee Water Testing for Hydroponics

Hydroponic systems rely on carefully managed nutrient solutions to supply plants with the elements they need for growth.

Monitoring pH and electrical conductivity is an important part of maintaining these solutions.

A suitable Milwaukee pH tester can help monitor acidity and alkalinity, while an EC or TDS meter provides information about dissolved nutrient concentration.

Regular testing can help growers:

  • Monitor nutrient solution strength.

  • Identify changes in pH.

  • Check water conditions before adding nutrients.

  • Track changes in reservoir water.

  • Maintain more consistent growing conditions.

For routine hydroponic testing, a combination pH and EC meter can be a convenient option. Choose an instrument with suitable measurement ranges and a probe designed for nutrient solution applications.

Milwaukee Water Testing for Aquariums and Aquaculture

Water quality monitoring is essential for maintaining suitable conditions in aquariums, fish farms and aquaculture systems.

Different aquatic environments require different measurements, depending on the species, stocking density and treatment processes involved.

Milwaukee instruments can help measure several important parameters:

  • pH: Indicates the acidity or alkalinity of the water.

  • Dissolved oxygen: Measures oxygen available in the water.

  • Conductivity: Provides an indication of dissolved ionic content.

  • TDS: Measures estimated total dissolved solids.

  • Temperature: Helps monitor thermal conditions.

  • Chlorine: Supports testing where chlorine monitoring is required.

The correct instrument depends on the parameter being monitored and the required measurement range.

For more demanding aquaculture monitoring, a combination of handheld meters and dedicated monitoring equipment may be appropriate.

Calibration Solutions, Replacement Probes and Maintenance

Digital water testers require appropriate calibration and maintenance to help maintain measurement performance.

pH electrodes, in particular, need suitable cleaning and storage. Allowing a pH probe to dry out or become contaminated can affect its response and measurement reliability.

GroAqua also stocks Milwaukee accessories and maintenance products for selected instruments.

These may include:

  • pH calibration buffer solutions.

  • Electrode storage solutions.

  • Probe cleaning solutions.

  • Replacement pH electrodes.

  • EC and TDS replacement probes.

  • Dissolved oxygen membranes.

  • Electrolyte solutions.

  • Other model-specific replacement components.

Calibration and maintenance requirements vary by instrument. Always check the manufacturer's instructions and confirm accessory compatibility with your meter before ordering.

How to Choose the Right Milwaukee Water Tester

Before purchasing a Milwaukee instrument, consider the following:

  1. Parameter: Decide whether you need to measure pH, EC, TDS, dissolved oxygen, temperature, chlorine or another specific parameter.

  2. Application: Check that the instrument is suitable for hydroponics, aquariums, aquaculture, laboratory work or your intended use.

  3. Measurement range: Choose a meter with a range appropriate for the samples you need to test.

  4. Accuracy and resolution: Compare the manufacturer's specifications to your testing requirements.

  5. Calibration: Check whether the instrument uses manual or automatic calibration and which solutions are required.

  6. Probe type: Confirm whether the electrode is integrated, replaceable or connected by a cable.

  7. Maintenance: Consider the availability of replacement probes, membranes, electrolyte and cleaning solutions.

Choosing an appropriate instrument and maintaining it correctly helps support consistent water testing.

Buy Milwaukee Water Testing Equipment at GroAqua

Explore our range of Milwaukee Instruments at GroAqua, including digital pH testers, EC and TDS meters, dissolved oxygen instruments and specialist water testing equipment.

Whether you are managing a hydroponic nutrient solution, monitoring an aquarium, maintaining an aquaculture system or carrying out routine water quality checks, our collection offers instruments for a variety of measurement requirements.

We also stock selected Milwaukee calibration solutions, replacement probes and maintenance accessories to help you care for your equipment.

Browse the collection and compare the specifications to find the Milwaukee water tester suited to your application.

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