In the winter the air going into the pond should be thru a diffuser that is placed between 1/4 to 1/2 the total depth of the pond, not the summer one that is in the deepest portion of the pond. Fish need a warm (relatively speaking) water refuge for the winter.

I prefer 24/7 rather than cycle it.

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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).