Maintaining Proper CO2 Levels In A Vacuumed Room...

Hello all, I've got my setup mostly finished and I wanted to see about keeping my CO2 levels proper. I have a 6x7x8 walk-in closet vacuum sealed with a single exhaust coming out of a portable AC unit in the room. The single exhaust is connected to an inline fan that jets the hot air out of the back of the AC unit, effectively keeping the room cool. How vacuum packed is the room? Well, when I walk in, the door is noticeably harder to open than when the fan is off. I have insulating foam coated in the door cracks to keep it sealed.

HOWEVER, I am concerned that because the room is now a vacuum that any CO2 being shot out of my tank will immediately be sucked out and not helping the plants. I have the CO2 tube placed directly above the rotating fan I have in the room, so that the CO2 is directly distributed evenly to all the plants. The rotating fan is about 2.5 feet off the ground, almost perpendicular to the wall (*slightly* pointed down). The fan is about 3 feet away from the front of the AC, perpendicular to it. If I am not mistaken, the AC takes air in from the ground, as well as in back of it, so I don't think it should be directly sucking in the CO2.

How much CO2 am I giving them? Well I have it set to go at 2.5 cubic ft/hour for 8 minutes every 1.5 hours during light period. During dark period, it stays off.

How does my setup sound? Please only experienced CLOSED-ROOM GROWERS respond. Your replies appreciated.

For others with similar CLOSED-ROOM CO2 QUESTIONS, this thread could also be a place for those. Peace.

bump bump you guys must be lazy stoners not wanting to reply

does having a vacuum sealed room affect your plants?

I'll post back tomorrow once the lights go back on and see how the ladies are doing. As long as they're getting the CO2 it shouldn't be a problem. I might need to up the levels a little if it's getting sucked out. Suppose a CO2 tester is the only legit way to know for sure.

Here is my logic from the facts I know:

(a) CO2 is heavier than the other air in the room, so it will sink to floor by the plants
(b) the fan should keep the CO2 circulated throughout the plants, effectively giving them "fresh" air

voidmaster said:

bump bump you guys must be lazy stoners not wanting to reply

Click to expand...

I just went through this problem. I sucked an entire C02 bottle dry in just 36 hours.

I fixed the problem by putting my A/C outside the grow room, adding an electric damper and a temp/c02 controller . In my situation I had an adjacent closet I could use. You could do this for any room I suppose.

Here is before when I had the A/C in the room.





Here is the pic of the A/C in the adjacent closet.



Then I installed a temp/c02 controller



When the temps reach 87 degrees, my controller turns off the C02, opens the damper and turns on the exhaust fan. The suction of the exhaust fan draws cool air from the adjacent closet. When the room gets cooled off, the controller turns off the exhaust fan, closes the damper and turns the C02 back on. With power to the C02 outlet, my C02 meter then monitors and maintains 1,500 ppm in the room. I've been maintaining temps of a rock solid 85 degrees which the plants seem to like with c02 enriched room. It takes about 1-3 minutes to exhaust the room and it will remain sealed for a good 8-10 minutes before the next cycle. The C02 controller also turns the C02 off when the lights go out. I was frustrated for days trying to get the room right. If you want it to be efficient, you gotta spend the money and buy the controllers. My current system uses a full tank of C02 about every 4-5 days which is about $10 a week to maintain from the local welding shop.