If you have electric on the property I think you will be spending less $$ with better results with electric aeration and water pump. You can have the pump hooked to a float switch that will keep the pond at the same water level.

A client had a winterkill with a windmill aeration system in one of his ponds while his other ponds with electric (grid) aeration systems did not experience a winterkill.

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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).