IMO You are going to need to add black dye until the DO drops to zero which indicates respiration is equal to or exceeding DO production. And then you still may have some natural production of DO. I think ideally, at the start zero DO should be maintained for at least 24hrs if not longer to verify DO production is minimal or equaling respiration. DO should be measured in every 6" of depth, if not shorter intervals. Photosynthesis and diffusion of oxygen from the atmosphere are two big producers of DO in natural waters. I'm not sure your plan is scientifically feasible in an atmospherically open exposed natural pond - too many variables IMO. IMO the best way to test DO production of a new diffuser system is to use the same methods or earlier studies. This makes data more comparable as in apples to apples.
Last edited by Bill Cody; 12/18/17 10:03 AM.
