Leaves curling

The leaves on my plants seem to be curling.. i've heard due to under or over watering but how do I tell? I'm also growing under an LED light could that affect it? Also when should i move them from their vegetative state to their flowering stage? I'll post the pics soon! Thanks!

waiting on pics man..

Curling in which direction? (up, down, side ways??)

which hydro method?

What nutes / watering schedule?

how about your vitals? Thats ph, res temp, and ppms...

We can only help you if can provide us with a more detailed view to which you are working...

--peace