What size tank do you use? Is it expensive and how long do you run if for, or is it multiple times a day on a timer? I don't remember you running any co2 before, is this something new?
I have a 20lb tank in a 8 x 8 x 8 room with an auto pilot. The auto pilot is set to 1100 +\~ 100 ppm. It comes on when the lights come on and shuts off when they go out. When this tank is empty I will leave it off until next summer
