New, and my first grow

Hello all! Im new here, and new to growing, so just wanted to do a quick hello and get some opinions/help with my first grow. I've got a female green crack, sprouted from seed. She first sprouted on june 22. I have it in a 2×2 space, running 150 watt HPS, and aeroponics with top feed. Anyways, things have been mostly going well until this past Sunday. I was doing my daily check, and when I checked the roots, they had a brownish slime covering them. There was some foam on the surface of my reservoir, and some dark either black or brown spots at the water line. I immediately started doing a water change, and ran some 3% peroxide at about 7 tsp for 2.5 gallons along with fresh nutes. I did use 35% food grade diluted down to 3% per what I found online. I did notice a lot of the slime seemed to go away, but then this morning it was starting to come back. I couldn't stay to do another water change, so I added another tsp of peroxide hoping that would help. The plant itself still seems and looks really healthy aside from the roots (they aren't terrible yet, and still mostly white), but I want to take care of this before it gets beyond my abilities here. I've attached some pics of the plant, I don't have any of the roots, but can get some later when I'm home from work. Any help, or suggestions on what else I can do would be greatly appreciated