cannoeing leaves??? wtf (pics)

For the last two days my little master kush girls from seed started to curl up while its not too bad yet i want to jump on it asap. i heard that its genetic with some strains. Im feeding them general hydroponics growth strength and my rez is 10 gallons but I mix it to 6 gallons cuz ive burned them before. ppm is 830. My temps range from 75-83 and humdity is 45-55% but heres the problem my rez gets to 82
I just moved the light (600w mh) to about 36 inches from the tops. its mostly on my matster kush but i have ice growing to and they seem to be ok. i dont want to stress them cuz their feminized and i dont want them to hermie later. Please help. and if you have any tips or help feel free and please no A$$holes im a noob at this.

you need to keep your rez temps down there to high i keep my any were between 70 and 60 75 should be the highst it should get i know that its hard to do that i keep a shit ton of water bottels frozzen and right before its water time i bring it down also try keeping your rez off the ground and out of the ligbt

so you keep frozen water bottles in the rez and rotate them out as they get warm? does it damge the roots

No it won't damage the root's I run a chiller at 63degrees 7/24 with no issues. When leaves curl like that it's, to close to the light, to much water or to much food.

you think 830 ppm is to much food? as far as the water the roots touch the water and i also have sprayers spaying them on a timer 30 on 30 off i moved the light so hopefully that helps i germed them on memorial day and they were doing so good but now to think of it i did bump the feeding schedule up and thats when the problem started i was doing 30 on 60 off and it was cool but what about those brown spots?

help? please someone??