I have an area of about 4x5 feet with a 4 foot ceiling. if I move my plants right from the cloner into the flowering stage to keep them short, I think I should have enough room. my question, should I get a 400 watt HPS or invest the little extra money into a 600 watt HPS to get tighter buds? or.. is this a bad idea with the low ceiling and will more likely just burn the plants?