Thats suchs BS ! i have a 400 watt from HTG im first using the Metal Halid bulb 39,000 lumes its already 2 foot tall and growing massive ! i have a closet space of only 3 feet wide by 5 feet long by 8 feet high ! yea you know im gonna grow a closest monster ! p.s. 18/4 hours watering ever 3 days with one gallon of water with 3 to 5 drops of superthrive full strengh nuts " better gro " 25/14/13/ i have a 1 18 inch rec. fan and a 4 inch exhaust fan my temps stay at 82* to 76* during the day 76 in the morning till about 1:00 then 82 after 1:30 when the house is heated up.