Buffet,

Why do you want more CFM in summer? If you are just trying to increase the DO, wont the fish die in winter when the DO of summer can't keep up? If you want more turnover you could set up the rig like HighFlyer and George did with the Kasco 12v surface aerator with a solar panel and a battery.

Second, how much CFM do you run through the quad diffuser? I don't know what is better, more CFM through one vertex head, or a lesser amount through many heads.

Third, what type of buoy is holding the quad in the water table? What if you had a black buoy holding up a black piece of pipe or square tubing? I was thinking it would work like the big boulders that are surrounded by snow year round. The sun heats up the boulders and the snow closest to the boulders melt. This would mean it helps get a hole in the ice for you.

Fourth, with your electric production, wouldn't switching to Lithium help out in that regard? Or do your temps get too cold for lithium?