If the pump breaks down and quits the pond just goes back to being a pond without aeration.
4' depth would be a recomendation for winter to keep a hole in the ice.
A slow start up procedure is needed in deep water in an old pond so not too much toxic water is mixed in all at once.
I'm in Kansas instead of Iowa so will let someone closer to your area chime in, but for summer aeration the idea is 1. keep water mixed so it does not stratify preventing the possibility of a "turn over" event and resultant fish kill and 2. keep water mixed so oxygen gets to deeper levels so fish have more usable water.
The only way I could see the aeration quitting being a problem is if the carrying capacity of the pond increased over time to take advantage of the additional aereated water and the resulting fish increased population were forced into the upper water as the thermocline established the fish would be crowded into a lesser amount of water.
But I am no expert. The experts may have a differing view.
Last edited by snrub; 07/09/17 12:11 AM.
