With all this moving water, what about water wheels to power small air pumps. Just a thought.
It's a thought but you would loose a lot of energy in the conversion. What I did is: On my pump there is a "T" fitting at the output of my pump used to hook up a frog that was suppose to sit beside the pond and spit water out of his mouth. It runs off a 1/4" line. I just hung the frog up so the water shoots back into my FT from about 20" away. That and the siphones draining back into the FT have been making more that enough aireation in my water. Now I only have 20 bluegills in a 100 gallon tank. When I up my stocking rate then this might not be enough but it's what is working for me right now.
I agree with Dan. I uploaded a picture of a simple tee off of the pump in my system. It provides plenty of extra air and water movement. And then the bell siphon of coarse adds plenty as well.
Not from need,- just to use the movement of water to supplement. It's free.
Design your system to use an air lift. You oxygenate the water and move it with the same pump.
windmill works good over 5 mile pr hr