Your being in TN and for a 1.5ac pond at 25 ft deep with a good aeration system having 2 diffusers run 24/7 the bottom water IMO will be within 3 to 4 degrees of the normal TN surface water which during July-August will be 80F and some years a surface 85+F; 20 degrees too warm for trout. Bottom aeration is designed to create good bottom to top whole pond circulation one turnover per day. Even i/2 turnover per day will make the bottom water too warm for trout. You conclude "I would say at 25ft the water would stay pretty cool...." In practical application this will not happen when with diffusers in the deepest area run 24/7.

Last edited by Bill Cody; 08/24/19 08:24 PM.

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