Strange Problems

So I've been growing for a little while and only recently (the last two grows) some of my plants have just flat out died in about 72 hours. I tried 1/4 strength nutes and they didn't rebound. Tried straight water and it didn't work either. It was real weird. They just dry up and die. They won't take up any water or anything. I know, this is very little information. Basically, all nutes and ph are good. They are in 5gal bubble buckets and under 1000w lamp. Temp is a little high at 85 degrees but most plants are thriving while a few do what I have described. Only happens in the last couple of weeks of flower. No, I won't post pics. Sorry but I'm too paranoid for that. Any ideas?

I blame OBAMA

no way to tell if you dont post pics yea your just paranoied as long as there isnt anything in you pic to give away your possible location you will be fine

Don't understand why you won't post pics, without them it's hard to judge the problem. One can only guess.

if your roots are in the water, i call bullshit
if not, get the water to your root level before you get under those thousands
ph in dwc is 5.8-6.5

Here's one: Got five sisters in the 6-7th week of flowering when one decides to revegitate. What causes that?