Most growers that us CO2 in their grow room typically use a timed release system; a control box that released compressed CO2 from a tank. CO2 tanks can be purchased from your local welding gas suppliers. Once you have a CO2 tank, you need a CO2 regulator and a CO2 controller. The regulator will determine how much CO2 is released and the controller will help create the perfect CO2 conditions. For smaller spaces, you may want to try small CO2 canisters, which are more rudimental systems that disperse CO2 for up to two weeks at a time in spaces 12x12 and lower. Many climate controllers can help regulate multiple functions such as lights, CO2, humidity, and ventilation. JUMP TO CO2 CONTROL