LL is right. 1 plant leaves no margin for error. I suggest 3 but keep them small. 4 weeks in veg maximum and then on to flower. Also, you need to think about ventilation. Even one plant will stink up your house. Or perhaps it doesn't matter? Your question about light cycle suggests that you have not done your homework. Start reading! The threads in my signature titled Room Setup & Fan Sizing, and A Beginners Guide to Growing will help you save time, money, headache and face. Read everything.