The Charles Austen Enviro ET40 is a powerful, oil-free linear diaphragm air pump designed to provide a dependable supply of air for pond aeration, aquaculture, hydroponic growing systems and other low-pressure applications.

Delivering a rated airflow of 40 litres per minute at 0.12 bar, the ET40 is well suited to installations requiring more air capacity than a smaller pond or aquarium air pump can provide. It can supply multiple air stones or diffusers through a suitable distribution manifold, making it a practical choice for larger water systems and multi-outlet setups.

Using Charles Austen's energy-efficient Green Drive technology, the ET40 combines high airflow with a relatively low power consumption of just 30W. Its compact, weather-resistant construction makes it suitable for a range of indoor and outdoor installations when correctly positioned and protected.

Key features

• 40 L/min airflow: Rated air delivery of 40 litres per minute at 0.12 bar.

• Energy efficient: 30W power consumption.

• Oil-free air supply: Linear diaphragm pump technology provides clean air without oil lubrication.

• Weather-resistant construction: Robust, compact housing for suitable indoor and outdoor installations.

• Continuous or intermittent operation: Designed for applications requiring regular or continuous aeration.

• Multiple diffuser applications: Can supply several air stones or diffusers when connected to an appropriately sized manifold.

• Serviceable design: Replacement service kits are available to support routine maintenance.

• Rubber elbow supplied: Manufacturer information identifies a rubber elbow as part of the ET-series fitting arrangement.

Suitable applications

The Enviro ET40 can be used in a variety of aeration applications, including:

Ponds and koi ponds
Provides an air supply for pond diffusers, helping to circulate and aerate pond water. The actual aeration performance will depend on pond depth, diffuser selection and system back pressure.

Hydroponics and deep water culture (DWC)
Suitable for supplying air stones and air domes in hydroponic systems. Its 40 L/min output makes it useful where several growing containers or aeration points need to be supplied from one pump.

Aquaculture and fish systems
Can provide air to multiple aeration points in suitable fish-rearing and aquaculture installations. Select the diffuser arrangement and airflow distribution to suit the system's oxygen requirements.

Wastewater aeration
The ET series is also used in wastewater applications where a reliable, low-pressure air supply is required.

Technical specifications

Installation and maintenance

Install the pump on a stable, suitable surface in accordance with the manufacturer's instructions. Use compatible airline, fittings and diffusers, and ensure that the total system resistance does not exceed the pump's operating capability.

For multiple outlets, a suitable air distribution manifold can help divide the airflow between individual diffusers. The airflow available at each outlet will depend on the number of outlets, airline dimensions, diffuser resistance and operating pressure.

Charles Austen recommends servicing Enviro pumps at least every 18 months. Replacement service kits are available and routine maintenance helps keep the pump operating correctly.

Why choose the Charles Austen Enviro ET40?

The ET40 is a practical choice when a smaller air pump does not provide enough airflow for a larger pond, hydroponic system or multi-diffuser installation. Its 40 L/min rated output, 30W power consumption and serviceable construction make it a useful option for users who need dependable, higher-volume aeration.

Choose the Charles Austen Enviro ET40 for a compact, oil-free air pump delivering 40 litres per minute for pond, aquaculture and hydroponic applications.