I know co2 is important and it helps cool the room and can almost double growth rates but I you don't the couple bucks it costs for a co2 unit and u were gonna do the dry ice thing how do you know how much is enough? Is too much a bad thing?(I'm sure it is as with almost every aspect of growing,besides love) what are if any signs of co2 poisoning? My method would be a cooler filled with dry ice some holes drilled in it and tubes running out to the room and hit with a splash of warm water when u need a dose of co2. Would this work? 4x4x8 l w h