Thanks Cecil,
So what is the difference where the 2 posts above had even water temps from top to bottom and you are able to keep your water at 60 even with diffuser? Your pond is smaller so the diffuser should have an even easier time of mixing the entire water mixture to equilibrium? It must be you replace cold water fast enough to keep it cool.
I'm experimenting with running mine 2 different ways. The last few weeks I'm running it say 30% capacity using a valve that I adjust with a crank that twists in and out. If I 'choke' it down, I can save water pressure for other needs, and can run 24/7. Downside is it creates turbulence or noise in the valve area in the house and it sounds annoying with all the gurgling from my basement. My brother who does pump performance curves all day tells me today that it is far better to run the pump wide open with the valves all open so that the pump can get higher up on the performance curve and really push the water. He figures even if I can only do that for 4 or 5 hours at night I might pump more water and less work on pump.
Make sense. Maybe the trick then is to run the aerator at night, and add lots of cold water. I don't need RBT range cold water but I thought keeping it a bit under ambient summer air temps might make the fish more comfy.
