If you have aeration in your pond, you could also move the winter diffuser so that the water is kept open around the siphon. The water should be warm enough so the water in the siphon doesn't freeze.

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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).