It looks like heat, over watering, or nutrient lockout.
I'd use Hydrogen Peroxide, and get them back on a normal schedule.
psteve Reviewed by psteve on . NEED HELP WITH PLANTS PLEASE !! Can anyone tell me what is wrong with my plants 15 x 15 room 3 x 1000 w lights PH 5.6 - 6.1 PPM 800 Flora Nova GH nutrients I didn't go to the room for 48 hrs and before they were all standing tall , the leaves erect into the lights. Now plants look droopy . leaves curled inside ( nearly closing in some ) and definetly look sick. Rating: 5