A fan similar to what cools your desktop computer is the type of fan that is used. Check with the mfg to see about the warranty on the compressor, what they will cover and what they won't.

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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).