David,
The real answer is "it depends." The type of diffuser and the depth govern the air lifting ability of the air. So if you have really small bubbles in a great pattern, like what vertex diffusers offer, you can move a lot of water. Vertex has a chart to show you how many gallons their diffusers move depending on depth. Also there is a range of output that works best. Too little air and you get no appreciable movement, too much air, and the bubble size degrades. So like most things, getting to the Goldilocks zone is very important.

With all that said, there is a simple way to check to see if you are mixing your water without knowing anything but the temperature. If the water temps are not nearly the same from top to bottom, you are not mixing your water completely. If the temps are nearly the same it is possible, but not assured, that you are mixing your water.

If you know the diffuser pattern and the manufacture lists the lifting rates at a given CFM and depth, you should be able to easily have your answer.

So for the WAG,

I would use 23 acre feet
the two diffusers at 12 feet
the four diffusers at 10 feet
and the windmill

With all that said, You are cycling you pond in.....

Somewhere between 12 and 19 hours of run time at rated output.

Your milage may very...

The real question is where did you buy your system and what did they say about its capability when you bought it? Did they size it for your pond? What were the advertised lifting rates? If you really want to know you should talk to the company that sold you the system.

Brian

The one thing is the one thing
A dry fly catches no fish
Try not to be THAT 10%