In a nutshell, you have to know how many GPM each diffuser station will lift, and know the gallons of water in the pond. Size the system to get a minimum of one "turn" of pond water to the surface every 24 hrs, that means if you run the compressor for one hr. per day or 24 hrs. per day.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).