I'm not sure how to read the performance chart. How many cubic feet of air is the output at 3 psi? Did you put an airline adapter on the pump and immediately jump to 1/2" or 5/8" ID airline from the pump to the pond? Or are you running the 3/16" line to the pond?

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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).