sounds to me ,like your plants didn't like the bad hydrogen peroxide. the 2% peroxide has allot of impurities in it. thats why the hydrazine is 35% much more potent and clean. that red stuff might be red algae or possible a bad wash from your initial hydro tron wash. you Did was the hydro tron before using it correct? in any case I think if you continue with a mild hydrozin and a quarter or half nutes till everything corrects its self it should be ok. don't flush no more if it is not helping, you can keep the hydrazine in the res with everything else just at a much diluted ed level. Did you wash the hydro tron before using it? cause this can cause Ph fluctuations and some things you are describing. doesn't sound to bad though, I think they will pull through.