Thanks doc. Ya I'm planning on getting two to three grows under my belt that way I have a good baseline. I was planning on using natural gas but maybe a tank would be better control of room temperature. Reason I didn't even consider using a tank for Co2 was cause I was thinking I would have to get it refilled every few days?!? How long do you think a tank of Co2 would last before having to refill?
depending on size of tanks and most importantly room size here this will help you figure out lots lol
Here is how my room is set
Grow room area: 1890 cubic feet
Amount of CO2 required: 2.5515 cubic feet
On time: 153.09 minutes
At this flow rate:
If you are using a 20 pound CO2 bottle with a regulator, it will last 174.8 hours.
If you have a CO2 Generator a 5 gallon propane tank will last 540 hours.
http://www.hydroponics.net/learn/co2_calculator.asp