Hydroponics Beginner - 12/12 Flowering Phase (Lemon Super Haze, NLxBig Bud & PPP)

High yall,

I got a simple question. It might sound really stupid but f**k it I need an answer because I am going to start growing in first hydro grow tomorrow.

I got some space problem, the room is really small so I would like to veg the plants for a week on 18/6 and then start the flowering period on 12/12.

Here is my noob question :
- Is it the whole hydroponic system that has to be on 12/12 or just the light ?

Plus, having some Lemon super haze, would it be a problem to try to grow it in a small space (sativa strain) or could it be taken care of by vegging only 1 week as I plan to do ?


THANKS IN ADVANCE FOR THE INFO !

++

Just the light ..

watch night temps make sure its not to cold

sativa in small places is never the best of idea.. i suggest training it