If you want the best LED light then go with the Lumigrow ES 330 watts, it is a true 600 watt HPS replacement and can grow some fantastic plants all the way to maturity with no real disadvantages compared to HPS. Uses literally half the juice and only produces a fraction of the heat. Also lasts way way longer. You can get them for $1200 or so each from the company direct (lumigrow.com) and one will effectively cover a 4 x 4 area when they are overlapping or 3 x 3 by itself. So to cover say a 12 ft by 12 ft square area completely you would need 9 of them but potentially could easily more than pay for them with the first crop several times over. Assuming of course this is a legal grow for medical purposes only by licensed caregivers. I'm factoring in empty space for room to move around the garden or through it, airflow and equipment, that's why I'm saying 12 x 12 instead of your total room size. :hippy:

Put a General Hydroponics Eurogrower (the complete version) under each light for 8 big plants x 9 = 72 plants total. At just a mere 1 ounce per plant (plants of like 18" - 24" or so at maturity) that would be minimum 4.5 lbs of flowers per cycle WORST CASE scenario. More likely is 5 - 6 pounds per cycle with good high yielding strains and nutrients (use the 3 part GH Flora series & Lucas formula of 8 ML of micro & 16 ML of bloom during flowering) with just a total of 2,970 watts of LED going and very, very minimal heat.

If you need to ADD some heat get the biggest gas Co2 generator you can get and don't exhaust the air out but I would'nt exceed 1200 - 1500 ppm or so with it which will give you huge yields compared to without..9 of those LED lights will actually add about 15 - 20 degrees or so to the ambient temps Im guessing. Compare that to ONE HPS 1000 that would nearly do the same thing temp wise itself and heat could become a big issue really fast.