@OdlaFett Sorry bro been dealing with a lot of work and a family health issue that may lead to traveling. I get a shit ton of notifications and its a pain on my phone to try to go through them so alot of times i just miss em. By all means if you or anyone else miss me in a tag shoot me a PM I get much less PM's so its easy to keep up with. Just to give ya an idea by 11pm when i usually get to be till 7am I will get over 4 pages of notification so lately i have been missing alot since i'm also not on for periods of time but just pop in to catch up on the common threads im in. Its not root rot, its likely staining but could also be some bacteria. If its not slimey or smelly its not to worry. Cal/Mg, and some additives will stain.
What are you using in your system in terms of nutrients, additives etc.? It could be a bacterial bloom not all bacteria is bad and lots are beneficial but just need to be cautious either way.