Then you have fungal mold or fungal rot. It happends sometime you need to do a full cleaning of your system with Bleach.

If they are not dead yet try some H²O² to clean the roots and give them a shot. Mold is bad and will kill you so be very careful.
Zandor Reviewed by Zandor on . aeroponic help :confused: been growing for awhile now,but i am trying a new set up.Have 25 site (5 tubes 5 per tube) aeroponic system i made.I am having trouble with what seems like damp off (tan slimmy weak roots) and black mold in the tubes.Clones have been flower for 2 weeks (did real well first 5 days)now they are in bad shape.Growth has stopped completely.They can still be saved i believe if i can get the problem takin care of. I m using: GH flora series and a little superthrive 1000w Rating: 5