That pump run time issue is still a big question mark with me, as is discussed in the link above. May need to revisit that thread. Since I put the new pump in, I don't need to run 24/7 for enough turnover (and I would prefer not to have the electricity bill for 24/7) but then the question looms, what hours to run.
Right now I am running from about noon to 6pm, which is enough turnover for this early season and I am actually trying to warm the water rather than cool it. But when hotter temps come I will increase the run time to probably 12 hours total. Then when it gets to July/August and heat waves will probably go to early morning till noon then again a few hours after 5pm to try and get adequate turnover rate but not excessively heat the water.
There is a good chance I am doing it all wrong. My idea is that by running the system during the daylight hours the phytoplankton are producing maximum O2 and I am moving low DO water up to the top for the plankton to do their job on and drawing highly oxygenated water to the depths as an O2 sink for the over night hours. This is against conventional wisdom and is probably wrong. But we will call it an experiment if I have a massive fish kill and everyone will learn from it.
