Looks like you're over feeding it. Do you know the PPM or EC of what you are feeding it? The curled up edges and brown spots makes me think you are feeding too much.
MasterKushy Reviewed by MasterKushy on . Plant Problem What is your experience level? (first timer, novice, experienced...) dumb novice Your Equipment: .1) Type and wattage of lights. (MH, HPS, CFL's, tube fluorescents, LED's) 1: 400w hps .2) Distance from tops? 2: ~8 inches .3) Reflector type? (cool tube set-up, bat wing, enclosed reflector, bare bulb...) 3: bare bulb Rating: 5