That seems like a lot of HP for that GPM. I'm pumping half that volume of water with 1/5 (or less) the hp. (I forget whether it's a 1 hp or a 3/4 hp motor)

Will you be somehow getting the well water mixed with air before it goes into 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).