they are 13 days old. my temp is at 72 humidity is at 40. why are some of them curling. a few of them look stunted ( havent seen any growing activity from them in 5 or 6 days) what can i do? at first i was feeding them a slight nutrient solution but then backed off for a 5 days using water only. a couple leaves have a few little brown spots. now i have them hooked up to the drip system i water every 8 hrs is that enough? how do i tell? MY LIGHTS ARE ON 24/7