Im new to the forum and I have a problem. I have been using this system for 2 years and have been very successful. So whats the problem? After a 1.5 lb per 1000watt harvest in Dec my last 2 grows have failed because of root rot. Same system cleaned meticulously ,same mother who is vibrant and healthy, clones were veged for 5 weeks in a mister system and were robust with healthy roots, transition to NFT with 1/2 strength nutes, water temp at 70 degrees, air temp no more than 80 degrees, 8" airstone in 40 gallon res. ppm 900 or less ph 5.7 , GH nutes exactly the same for 2 years and now I cant grow. 2 days after the plants are transfered to the NFT they begin to wilt, leaves turn yellow and they stop growing and what appears to root rot begins. I am sleepless now trying to figure out what the hell Im doin different and cant figure it out.