Is This Root Rot and if so What To Do? (pics)

Hydro grow. New RO water (from vending machine) with PH 5.9 and 1200 ppm nutes. They were a beatiful white before but just switched to bigger buckets with new water and overnight they did this. There is very dark layer that exist on roots that are above the water. Water temps should be fairly low (maybe 60?). Is it RR and if so what do I do?

Yes any browning of roots in hydro is rotting and it sounds like you have it bad, to correct the problem get some H2O2 at min 29% grade and add it to res every 4 days at 60:1 ,50% grade at 100:1 . This will fix the problem.Dont stop using it ,yes you need large containers to keep you going.

I talked to my local hydro and they suggested a few things. SM90 at 3ml per gallon, and 29% H2O2 diluted 10:1 to make 2.9% using one teaspoon per gallon. I'll see what this does after 2 days and report back.

i would agree normally, but that does not look like it to me, the bottoms look great, where as they would be brown and slimy if it was rot. no idea here sorry, could just be water staining.

I've had chlorine staining, this is not it. No, it's root rot. Roots used to be a clean white and now even the bottoms are straight and rotten looking.