1 hr before venting with fresh air
 

I am thinking about running co2 / I have a 700cu ft room. At what intervals should I should I fire the co2. I was told 6 times a day every 2 hrs for 2 min. Then to leave it for 1 hr before venting with fresh air. Does this seem correct? Also should I run the co2 when the lights are on or off or does it matter? I am having difficulty getting answers to these questions. Thankyou romulus@sympatico.ca

That sounds like as good of a calculation as any.
When the lights are on. co2 doesn't work in the dark.