Originally Posted by Bill Cody
There are also coarse bubble membrane diffusers. esshup used one this winter from Zoro.

Correct. IIRC 5" diameter diffuser. 5' below water surface. 1/4 hp Gast rotary vane pump. It opened and kept open an area that was about 50'-70' diameter and the other side of the pond had 8"-12" ice on it. I'd run it for a few days, then shut it off for a few days. If we were supposed to get snow, I'd fire it up and leave it run until the snow was over with. I didn't mind if the area froze over as long as it was clean, non-snow covered ice.

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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).