can i chime in here? i cant sleep at night when i know a member has/had root rot and had lost a crop before, you said you tried hygrozyme and it made things worse right? i know a few members here who have had this problem. at the price of $45 a qt, hygrozyme should be a cure all but its not if your adding it to a rez that already has pythium. i have had root rot 3 times and defeated it everytime with hygrozyme and store bought h202. but theres a proceedure that i came up with and works 100% for me and it will work for you. now that you use an aeroflo is should be pretty easy to remove each plant. first...pull a plant out and one by one, bring over to a sink run cold water over the roots and try to pull off any dead/dying brown roots and try to get asmuch slime off as possible, Second...spray roots with a peroxide mix (3% @20ML/qt) . Third..heres the tricky part, you dont want to put your plants back into your system until you have cleaned it out completetly, you need to find a place to sit your young plants for a little while, i use a cloner or any cutout. go scrub your rez out with hot water and that peroxide solution, once rez is scrubbed put back together and run the hottest water you have with a stronger peroxide mix or atleast the same one as the spray, this is key the hot water along with being run thru the sprayers will help blow it out of the lines. i would say run the systm for maybe 20mins atleast. put plants back in and add HYGROZYME along with fresh res-plain PH'd water. now i know it didnt work before but heres how it goes, when you add hygro to a root rotted system the roots get worse! the water starts to look like sewage......this is fantastic! this shows that the hygrozyme is working, but heres is the key to its use for now, since you are running a recirculating hydro system that nasty sewage water will be shot back at your roots, to expidite the recovery of your roots i suggest you change the res daily for the next 5 days, i know its a ton of hygrozyme but it will save your crop, just dont fill the res all the way, just enough to operate the system cus it would be a waste of hygro...within 5-7 days you will have brand new roots like gangbusters! this 5-7 days are PH'd water and Hygrozyme Only, no nutes. for future reference you need to find out why you keep getting root rot. i suggest you use hygrozyme with every rez change and you will never get this again.