Smallwater, that will outgass the well water and add O2 to it, you are fine doing that. Like CJ said, you will most likely see a greater temp change from a heavy rainstorm or a prolonged cold front than from the water that you are pumping 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).