Gast rocking piston Deep Water Air Compressors are the best choice for deep water aeration. High pressure output and constant volumes make these compressors perfect for ponds from 8' to 35' deep. Dual aluminum pistons, hard-coated cylinders and replaceable piston seals make these compact workhorses as long lasting as they are powerful. Replaceable air filter keeps dust and abrasives out for long life. Rubber mounting feet and sound dampening reduce noise and vibration.