Leaves are folding? Please help

My girls are about a month in a half old (currently in veg mode under 600w MH)
Today i noticed the true leaves folding inward and their leave tips are curling down.
Could use some insight as to why they are doing this.

PIC 1 & 2 you can kind of see the inward folding
PIC 3 you can see the Leaf tips curling down some

looks good to me!!! Their just lovin the light reaching soaking it in!!!

looks all g to me

check you temp at the top of plant they look like there to close to light

If anything it is very early nitrogen overload. Watch for more downward curl or blanched leaf tips indicating it even more. The canoeing is from heat stress. Raise the lights, turn on the fans and use water only - no nutrients - and watch the plant.

thank you for the input, its my first grow so id like to think I'm doing well so far. But i do have one question. I transplanted my plants from 1 gal to 7 gal on the 18th feb and with the fresh new soil ( fox farm ocean forest and Light warrior mix and some coco fiber added) i stopped adding nutrients to it with the fear of having nutrient burns ( did it once don't wanna do it again.) When should i start adding nutrients to it again?

No problems in my eyes, they do look a little hot though - not a bad thing in veg in my opinion.

relax leaves look OK
is normal to start out folded up like that then spread

in the flowering stage

How close is your 600? I would back it up 4 or 5 inches. See if it helps.

Looks like heat stress to me. Like other poster said to check your temp, put your palm between the light and top of leaves to determine the level of hot in between. And inspect any pests or fungi attack on the plants. Finally rootzone is very important...root system dont like too cold or too hot either.

make sure that your grow room have a good airflow and ventiliate etc.

and about when to feed, the plant's leaves will become light green color, its signal to feed time. Hope this will help ya.

happy gardening.