Yes, in the colder months the fish don't grow very much. Yes, FHM can survive in waters where other fish struggle, but if you haven't seen dead fish floating, then I doubt that you've lost a bunch.

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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).