Literature indicates that 4ppm DO is stressful for trout. However when the water is below 40F trout respiration decreases and IMO they can/will survive well in water at 4ppm and sometimes less due to the lower cold temperatures. Spring thaw will tell the rest of the story.

I think the trout from ice cover to late December will move throughout the pond and "recognize" the DO is slightly higher near the diffuser and open water. This should provide a DO refuge that is recognizable by the trout. I suspect when DO in the remote areas of the pond becomes stressing, the trout will collect or gather around the influence of the quad diffuser.

Last edited by Bill Cody; 12/29/17 12:51 PM.

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