Personally I've come to the conclusion that aerators put air into the water by moving water and exposing more of it to the atmosphere at the surface then they actually put in through the air bubbles. Then of course they can help circulate aerated air to other depths. I took the approach of putting my aerators in the deepest spot and running them intermittently to save energy during the summer and avoid super cooling in the winter. If you aren't running in the winter then the only reason not to run 24/7 would be to save energy. Wish I had the benefit of a DO meter. I would think you could establish a reasonable schedule for your aerators and start checking DO throughout a 24 hour period. If the DO stays high then cut back on the run time. I chose to run mine from midnight to 4am during the traditional low DO period and again from noon to 4pm thinking that this also could be a low DO period during the heat of the day. Don't know if my logic is sound but it has worked for 4 years and I only run 1/3 of the day to cut energy bills.

Gotta get back to fishin!