Wtf? Dwc root problem?

hey guyz I checked on the ladies this morning and this is what I found on one of them,(pictured below), its some kind of brown glob clinging to the roots. its not on any of the other plants in the same system, im already flushing the whole thing with r/o water, plus the plant, and its roots seem otherwise ok. I'm thinking it was the liquid karma I had in the rez, that stuff seems to settle after a while, should I not use it anymore? has anyone seen this before? and is liquid karma bad for DWC? I use gh flora series, superthrive, h2o2, and ( until know) liquid karma. Any advice would be appreciated.

Its the Nutes your giving it, I have had the same thing happen and I just left it, everything worked out fine, eventually it washed itself away.

thanks I kinda freaked out when I saw it cuz it was kinda nasty lookin. lol. + rep