Sounds expensive to recycle pond water through a pump and send it down stream and back into the pond. I don't think it would aerate nearly as well as your typical aerator working from the bottom.

It definitely would look prettier and that's why a retailer with plenty of cash can do it. But, for your typical pond owner, it doesn't sound like a viable solution.

0.6 acre pond / 13' max depth / Bonham, TX