You will be just fine with the RES in the pond. Best choice for a panfish in the pond to avoid nipping at swimmers. You have to get up into Michigan to get water that is too cold for RES. BUT, if you aerate and have the diffuser in the deepest part of the pond running during the winter, you can cool the water too much for the RES.

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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).