I have been posting a lot about rising pH problems. I found that the cause was that I yet AGAIN had some root rot. It wasn't nearly as bad as before. The equipment was very slimy, but it did not smell. The roots were only a little brown. I can not understand why this happened. I have replaced all of the equipment including the reservoir, channel, tube and pump. The channel and res were completely dark and very well light sealed. The res temp was at optimum oxygen solubility temperature 68F. I had dosed it many times with Hydroguard beneficial microbes. Perhaps the microbes helped a little and that is why it was not as bad this time, but I have taken every precaution I can think of to stop Pythium and I still got it. I have yet again changed the res and replaced all of the equipment, washed the roots, and I have switched from Hydroguard to H2O2. I have applied a full dose of H2O2 to the res and I will be applying a 1/3 dose every day from now on. I am not satisfied at all with this because everything I have read indicates that microbes are a much better way of dealing with Pythium than H2O2, and also have lots of other benefits that I will now be missing out on. Thanks for all your guys help and cross your fingers for me this time!