No one wants to answer you because you obiously haven't done any basic reading on your own.

But

You can leave your lights on 24 hr for the vegitative cycle of the planst life. Or up till its time to flower the plant. (Some do and some recomend giving the plants a break. If your using a Cab I would give it an 18/6 light cycle cuz its probs gonna get hot in there.

Add your hps If you like, more light bigger plants, but make sure that the temps are in the right area for that you'll have to read on your own. I would recomend using the CFls for Vegitative Growth and the HPs with the Cfls for flowering.

good luck

kd
kdspecial Reviewed by kdspecial on . quick question actually 2 quick questions. can i leave my light on my plants 24/7 till flower? and my next question is should i bother getting a 75 watt hps to add to my grow box? Rating: 5