First Time Hydro Grow, Having issues, help!!

I messed up from the beginning, I know now after researching. I started my seeds in 1" rockwool cubes, moved em up into 3" cubes before the transplant. I didn't ph the water for the first 21 days, tapwater was 7.2 for the first 21 days. had em in a propogator with 2-24W cfl's 12 inches above them. I got nervous and transplanted them in coco at 21 days and put them in the big tent under 400W MH's for the first week in the tent. had ph set at 5.8-6.2 daily, nute levels at 550. Ramped up nutes after they were 30 days old to 950 ppm after I began to notice a big change in a few of my plants and I've tried mag/cal, and organic nitrogen (smelly fish powder) to no avail. now almost all my plants are wilting and I'm at a crossroads and need some immediate help please. I know I'm new to hydro, some of you are probably shaking your head, but I really need some help or a nudge in the right direction. Thanks in advance!! Oh, and ALL the roots look bright white and fuzzy, so I know it's not a root problem and I just emptied the 55 gallon drum, scrubbed the crap out of everything and readded nutes with more cal/mag and nitrogen.

5x9 Gorilla Grow Tent
6" inline fan ducted through cool tubes and exhausted outside tent
2-1000W Cool Tube MH w/ xtra large wings
electronic dimmable ballasts 400W,600W,1000W
Big Boy drain and fill system 12 pots, 55 gallon drum
1 wall mounted oscillating fan
Co2 w/ controller 15 minutes per hour
2 passive air intakes
Fox Farm Nutes (bb,gb,tb)
cal/mag
medium is rockwool transplanted in cannacoco


Currently Running:
lights 600W MH 24" above plants 24 hours a day
fill and drain 4 times a day, 20 minute fill, 40 minute drain
temps run 78-82 degrees
humidity 42 percent average
ph 5.8
ppm 1000