I had been battling root rot for about six months after never having had an issue with it for years using my well water(.1ec and around6.9to7ph)in my flood and drain set up. Got to the point that my harvests were about one third what i was used to. Had limited success with s.a. ,hydroguard ,mykos,azos and great white but still wasn't seeing the response i needed. It helped but did not resolve the problem. Thinking i may have a bacterial or fungal issue with my water i tried the standard well shock treatment with chlorine. Flushed a bunch of ugly looking crap out of the lines after the shock and that seemed to help for a couple months but still needed to use a lot of beneficials to keep everything looking healthy. Got an inline uvc water sterilizer for constant water sterilization and have seen a significant improvement in root health and vigor to the point i have been able to stop using the beneficial additives and my roots have been exploding out the bottom of the rock wool like they did before this problem started. In addition my clones are rooting again in one to two weeks with 95-100%success and significantly better root mass. they were previously taking 3-4 weeks with about 50-60% success.i would definitely recommend getting an inline sterilizer mine was around 150 from Amazon and you may get a portable aquarium sterilizer to treat your reservoir as needed. It doesn't change anything about your water chemistry just kills all pathogens with the uvc. I have read that it may cause some drop out of iron if used in the reservoir due to the high uv levels. Btwi did some tests with rooted clones using the southern ag and hydroguard and did not see any difference using either,they both reduced root rot and increased healthy root mass.