When tackling the environmental side of the growing process, most find it particularly easy to overlook some very basic and extremely important aspects. It's very easy to find yourself getting the air circulation sorted and forget the little things such as air quality, temperature, humidity and odour to name a few. Improve air quality with CO2, add heaters and a thermo hygrometer to keep an eye on your temperatures, humidifiers and dehumidifiers to maintain the correct level of moisture, and odour neutralisers such as Ona gel will help keep the room smelling fresh.