nasty buildup on roots with 65-70 degree water PLZ HELP

And KP....if you think thats salt buildup, you may be looking at the wrong pic???? Or maybe Im crazy.

ok just put some hygrozyme in there and it was like i was mixing a cocktail in chem class lol i could visibly see more bubbles like peroxide on a cut. so im gonna check PH tomarrow and probably do another rez change on sun and the some more hygrozyme in the fresh solution.
Another thing i wanted to run by you guys, 200 ppm city tap water wouldnt add to this problem would it?? never had any problems with my ebb and flow or drip systems but this is my first DWC and my local growshop said that it "may" be contributing to the root rot.

Yeah theres really no way this could be salt build up because my nutes are at about 1/4 strenth and the plants arent suffering at all i actually just had to move my lights up this morning. i think i forced a small growth spurt by rinsing roots and letting them air out a bit the other day

By the way nice avatar bigbrew lol

Hey man, do you use the solubles Fox Farm products along with your liquids?

yeah but only during blooming these plants are just in veg

nutes are too high

im only using about 1/4 to 1/2 strenth depending on size of plants.. so thats like 3 and 1/2 teaspoons of grow big hydro to my 7 gal rez so i dont think im overfeeding em

I was wondering, How often do/did you change your res BEFORE the problem occurred? My tubs are not lightproof, but I religiously change the res every weekend. The fresh water is like cocaine to the babies...always a growth spurt fer 2 or so days....root rot smells like rotton eggs, or bad sulpher water. Had that happen and it wasnt pretty.....that was due to hot res water!

well this was a new setup but i let my water temp get to high and i think that + the light leak= nasty shit but it is clearing up nice so far with the hygrozyme in there so i think im gonna do another rez change today to get that nasty dead matter out. but it was only set up for a week then i started haveing problems but i dont think id let it go more then 2 weeks even if everything was goin good.