We have a customer that is using a single Gast 0523 rotary vane compressor (1/4 hp) to push air to 3 different ponds at the same time. 5 single membrane diffusers. That single compressor replaced two Koenders 1/4 hp compressors (that could only run 3 single membrane diffusers), and the Gast is pushing more than 2x the air volume of the two Koenders for half the energy cost.
BUT the Gast rotary vane isn't the one I'd recommend for a deep pond, that would be a Thomas Rocking Piston compressor. They can operate to a higher PSI than a Gast rotary vane.
Both the Gast and Thomas are easily rebuilt when needed.
: ) the OP is looking for a pump for his single .2 acre pond.
Which one would you recommend to him? The often here recommended '5 pond' Gast?
