If you have ice off, you could turn off the diffusers.

I'd move them back to deeper water once the chance of ice covering the pond for more than a couple of weeks in a row is 100% gone.

If starting them up when the water temp is 55°ish and below, then no start up procedure should be required.

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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).