I have two diffusers. One in the deepest part of the pond, and one that I suspend under a float at the 5' deep level. That way if the pond goes up or down during the winter, it will stay at the same depth. IIRC, the winter diffuser should be 1/4 to 1/2 the max depth of the pond. I set mine for 1/3 to 1/2 the max depth.

There's a pond that the client wants to feed trout all winter long. I'm going to add two diffusers to the compressor, and have them all on a manifold. I'll shut off the 3 deep diffusers, and turn on the 2 shallow ones. It will keep the water open in front of the feeder, and he can feed the trout all winter long.

I did basically the same thing in my pond 2 years ago and it worked fine. I didn't even have to shut off the diffuser, the trout fed on the pellets with the diffuser on or off with the same intensity.


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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).