I am far from an expert but I live in Northern Ohio and my family has many ponds.

The ponds that have windmill aeration my father and stepfather never did anything. They let it run as-is all winter long. As far as I am aware there was never any fish kills with this method. One pond was a bit bigger than 1 acre and about 25 ft deep. The other one is shallow 15 or less.

If you are concerned about it, you could hook up the hose for half a day, then unhook, gradually running longer and longer on windy days over a couple of weeks before leaving it hooked up.

Sadly my father is no longer around but my step father still is. I told him about how it's recommended to not aerate deep water in the winter and he was shocked by this as he hasn't had any troubles with the set-and-forget method, just grease in the spring.

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What I am doing in my pond is pump aeration in the shallow water right now in the winter to keep it open. I have a fountain that I put up for the winter, but it will be pumping deep water in the spring. I am told this isn't enough for my pond so I am looking into a Windmill option at some point.

I have had extremely good luck with Barley Straw in my Koi Ponds and will be using large bales in my big pond this spring. I want to get away from chemicals that build up if I can. I think it'll be better for the fish and other life.

Last edited by klingj8; 02/05/20 03:56 PM.