Room was later updated with 2 more hoods and a secondary trey all modified to be completly sealed on light movers room had a stand alone ac unit recirculating air.. room was sealed for best ppm 4 1k nex gens and 4 mh balasts nati gas co2 gen plummed off heater gas line all breaker and timer boards are homemade...2 wall mounted rotational fans also on first grow i used floure lamps onside to get the bottoms and sides to fill out.. was like sitting inside a chilled flower room..