I've NEVER had plants look as bad as yours did on the first page. Then again i never had a major pH issue and tried to incorrectly adjust it, or heat stress that bad.... We all were noobs at one time but wow they looked like shit.The plants are doing good at the moment. They still have a few leaves curled up but no major signs of risks there. I think it was a combo of heat stress, low humidity and weak ventilation. Allot of people in this thread are just guessing and declaring it as gospel truth..