Co2 Burner Run Time? Help

hey guys soo i saved enough money for a cd 12 burner.... they say by the calculations on the green air website.. it will fill my space to 1500 ppm in about 10 mins....in using a one car garage...18 by 14 by 9 my question is since i dont have a controller that is keeping track of the ppm in the room yet how often should i have my timer turn this bad boy on? every hour or every other hour when the lights are on..? thanks

15 minutes every hour while lights are on is what i prefer...
but i mean you could do every other hour too.

but i guess you can figure out your own schedule, all you need to do is mess around for a while until you get the fattest buds, just make sure not to use too much co2.

(better too little than too much - in my opinion)