Growing

hello this is my first time growing under lights . i have a 400 watt hp light and my plants are about 3 weeks old and about 3-4 inches tall. i wanted to know how far away do i keep the plants from the light ... and basicly what should i do , im used to growing out doors . what are things that i need to watch out for??? how do i know if my plants are goin to be male or female??? please help with everything

is your light well vented? if you were growin outdoor you should know when it's male or female don't you?

light should be about 30-40cm away from plant top, though this will vairy depending on how good the ventalation is.

search is your friend.

10-12 inches if you just have a standard 400watter,,,maybe a little lower if you have a oscilating fan blowing over the tops of ya plants,,peace

24 inches should be good if your plants look like the streching just for light then move them closer.
to tell if you have male or female you basically have to flower them unless you have a early flower strain. but males have pollen sacks and females have little white hairs.