That's my concern Tom. Eventually, the air temps may overpower the circulation and everything just keeps getting hotter over time and the whole pond overheats. At one time this summer my surface temps reached 99 degrees before I put in the system.

Running only 6 hrs at night, I've reduced the temp variance from top to bottom to only 3 degrees in just a week. That's why I'm thinking infusion of cooler well water may be my only option. I can maintain a full pond that way as well. Even with 10.5 feet of depth I'm 88 degrees on the bottom, 91 degrees 20" down.

.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!