Another vote for the comments above. I almost lost my Springer Spaniels because they went into the water after some geese when the ambient temp was -12°F. I have now moved my diffuser and strongly recommend placing the winter diffuser(s) so that there is open water all the way to the shoreline.

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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).