I am going to have a house to myself for 12 to 13 weeks. I am planning on growing 2 plants hydroponically. I'm thinking of starting them with a couple CFL's each during veg. and then adding in a 150 W HPS sun system for flowering. Is it possible to harvest in this amount of time? Any tips on reaching higher yields? Would it be worth it to buy a 250 W instead ($200 vs. $100)?