RobA, I'm reviving this thread because I'm looking into a windmill. I think you should do it, here's why 1) if you have wind, .5 to 1.5 CFM will be good for your pond, aeration 99.9% of the time is better than none. 2) Once you're up and running, the daytime circulation decreases the odds of nighttime DO crash. 3) after your initial purchase, it's a free benefit to your pond. 4) If you're like me, DO isn't a problem, you are doing this to increase productive water.
I'm not disagreeing that electric is better, but if it's not economical to run the line, the windmill option is far better than nothing at all.
