Pond Boss Forums MANAGING AN EXISTING POND Evaluating and adjusting fish populations fish kill

Plants create O2 during photosynthesis which obviously occurs during daylight hours. They respire during dark periods - this is when your DO levels get low, especially right before sunrise. Periodic aeration can work, but since DO levels are lowest during dark, that's when your pond benefits most from aeration. So, you got them switched around unfortunately. I don't know how much you're spending on electricity per month, but strongly consider aerating 24/7 when temps are over 60 as the fishery you've spent so much time and effort establishing and managing is certainly worth the investment.