Cecil- I have noticed the same thing as your buddy. With the camera down, I can watch lots of fish without any bites. I'll bet the fish are under some kind of stress. Could it have anything to do with super cooling the water?
My neighbor's pond is well aerated (maybe too much) and the same reactions from his fish.
If you or your neighbor are supercooling the water with too much mixing it most certainly could be stressing them. One of the first signs of stress is a fish that is not interested in eating.
