Pond Aeration


There are many things to consider when choosing the right air blower for your fish pond:


The water depth at which the air is released into the pond will determine the primary operating back pressure of the pump. For every 1 foot (300ml) of water depth, 0.43psi of resistance occurs

The table below gives the rated back pressure for differing depths of water:

Depth of water at the air discharge point BACK Pressure in PSI at this depth
1' (300ml) 0.43
2' (600ml) 0.86
3' (900ml) 1.29
4' (1200ml) 1.71
5' (1500ml) 2.14
6' (1800ml) 2.57
7' (2100ml) 3.00
8' (2400ml) 3.43
9' (2900ml) 3.86
10' (3200ml) 4.29


The total water volume of the pond is very important when selecting an air blower for your pond

A handy guide is that every 4000 litres of pond water will need 40 litres of air per minute to attain the correct dissolved oxygen level for koi fish., although the amount and type of vegetation and the number of fish in the pond will vary this slightly. If you are in any doubt, please ask your fish supplier.

For the rated pressures and airflows, please refer to the GDT AP series air blower data sheets for particular model information.

You cannot, however, get the MAXIMUM air volume AND the MAXIMUM pressure at the same time with any linear air blower. As the pressure increases, the volume f air pumped decreases and vice versa. Please see the Flow Data Sheet.


Some plants produce oxygen and release it into the pond water, whilst other plants don't.


Always site the pond air blower well above the pond water level to prevent back-syphoning when the blower is switched off and to prevent electrical accidents and malfunctions.