Ventilation and co2

Hey y'all, I'm just about to install my co2 thingamajig (with a co2 tank and so on) but I'm just not sure about how it will affect my exhaust fan. Now, I know one has to turn off the fan while the co2 is coming into the room, and I know how much co2 I have to put into the room (using the formulas concerning the room size and the flow rate etc), but I just don't know about the fan.

I'll put it to you: if I run the co2 tank for 1 minute every hour, when the lights are on, for how long before and after should the exhaust fan be turned off?

Maybe I'm being a dick about it, but I am worried about having my fans off for too long, as the temp can really rocket in the room.

Also, when the co2 is coming in, is it necessary to turn off the smaller, breeze generating fans as well?

And finally, does one have to inject it every hour? Which is to say, if I optimized the co2 levels every three hours instead of every 1 hour, would that be less good? (three hours being an approximate time for co2 levels to return to 300ppm)

Thanks in advance guys.

Any ideas?

How many plants are you growing? co2 isnt needed for a small grow in the closet. Ummm... i say catch a bird, clean it, put it in the room, release co2, slowly increase the co2, bird passes away, and turn down the co2 slightly from that amount. There now its safe to walk in and your plants will get optimal co2

Educational purposes with bird. Replace bird with a co2 meter or get a oxygen mask.

I have gotten great results in aeroponic without co2, and have never needed it. But, if I was going to do it, I wouldn't vent the room, only the lights.

intake->lights->outtake.

if it gets to warm you can use a small ac unit, and you also have to use a air filter - air doesn't get "stale", just polluted.

That is what I would do anyway..

I use co2 with all my grows except one of my last ones just to be a dummy. co2 saves about 4 weeks of grow time and will increase your harvest by 50-75%. I use my co2 tanks on timers along with your vent fans as they have to alternate and you have to have a damper on the vent so the co2 doesnt escape. You want the co2 levels to hang around 1500 ppm in the room. You leave the air moving fans going have one down low blowing up as co2 is heavier then air so it will sink and needs to get blown back up. I run my co2 2-3 minutes every hour during lights on period.Then every second hour I have my outtake kick onfor 5 minutes with my intake on aswell.This will take old air out renew the air then they shut off and the damper close the openings then my next co2 injection kicks in. You want all these to be timed against each other never with each other or its a waste. Temps will need to be higher between 85-90 max and only during lights on.The co2 shouldnt kick on during lights off but the in and out can still run.Good luck Its well worth it

Thanks filthyfletch, good advice. I've got a pretty big grow op, so the co2 would help.