Bill, I'd be interested in seeing a temp comparison to a pond that is near you with the same water clarity and depth vs. your pond. I don't know if the Geo system will change the temp all that much....... But that's just a WAG.

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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).