Even with keeping the snow off some of the ice, if it's oapque ice, not a lot of light will get thru the ice. I'd try running the diffuser in shallow water near shore (about 3' depth) away from where the kids ice skate. Run it right after the snowstorms pass. That should melt a hole open, and once it's open, shut it back off. The ice should freeze clear and let a lot of sunlight through for phytoplankton ro produce O2.

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