Im using GH 3 part. Like I said I had a slime/algae problem a few weeks ago and a littel h2o2 took care of the slime they are not slimy to the touch after treatment. It disapeared. It starts to show up after about a week or so but 5 ml of H2O2 takes care of it in a few hours. They smell plant like and they dont stink like something bad. Its just that some of the roots have really dark spots on them like bruises. See the second picture the root in the middle that is really dark. That is my question, if that is a problem that any of you have seen like root rot. I just want to make sure its nothing bad and just normal nute solution staining. My plant does not show any deficencies and looks really healthy but I read that root rot can be in healthy looking plants. Thanks for the help. Peace