Charlie, look here for the numbers,
O2 Table from YSI At 84f with no salt or Chlorine, about 7.69 PPM is what I read.
Actually highflyer you can get supersaturation rates from algae blooms that exceed that. I suspect that may be what is going on here if the readings are accurate. It would also explain low oxygen readings below that due to a combination of an algae bloom blocking out sunlight, and decomposing vegetation below from too aggressive of a herbicide treatment.
Anyone else concur? And no hard feelings if you totally disagree.
Cecil, charlie was looking for a maximum O2 level reading for 84f. While the maximum number is probably really high, the saturation level is a good place to start and it was the only table I could find easily to help add to the learning going on. If you have a chart that shows the MAXIMUM O2 levels, I too would love to see it. I also understand supersaturation, but I thought that might be outside the scope of this thread. While 50 PPM O2 is possible, the effort would be considerable (read extreme) and definitely not worth the cost or effort, besides, your fish would be dead of O2 poisoning long before then.
Maybe I am missing the point of this thread. Isn't it to help Charlie understand normal O2 levels and how killing all of your vegetation at once is a really bad thing? That the depletion of your O2 by decomposition is inevitable when you kill off all of your vegetation and unless you have the right size surface aeration to add the needed O2, If you don't have the right sized surface aerator during one of those events, you are likely to have problems (read fish kill).
Please let me know if I am wrong.
