Kelly, in the winter you want stratification. Warm water refuge for fish at the bottom of the pond. Water should be around 39�F there. Water can be in the low 40's directly under the ice, or below 39�F. If the diffusers are run from the deepest part of the pond in the winter, the whole pond can get too cold.

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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).