He said pH was fine and he had been neglecting his grow. Heat/cold won't do that. Over fertilizing does not display theses symptoms but under feeding will. He asked if they caught something, I said no in my own way. It's not always black and white and and you can't always find your answer in a book or on the internet. The problem here is 95% of growers cannot /will not, nor do they know what their plants are doing just by looking at them. It's called deducing , start with the obvious signs and build a case as info is learned... Unless you are fairly new you should be able to look at a plant and know exactly what is going on without ANY information or at least get real close. Sorry but this is just my opinion and I guess I'm very talented in knowing MY plants . good luck and harvest big.