I will let Bill clarify but I took his response to mean that because WB's pond is a trout pond, and since they do well in cooler water, that having that cold water during the winter wouldn't make a difference to them, vs. making a difference to say LMB and BG/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).