CO2 Exhale bag hanging height help

Has anyone used the CO2 exhale bags in there grow tents?

I’ve got mine hanging just above my plants, but I’m worried about it drying out or something? Cause it’s underneath my led light

Anyone know anything about them? Or have experience with them ?

Garbage. Not worth the money. Unless you are almost bleaching your plants in light. You don’t need it



The reason I’m using it, is cause my tent is underneath the stairs. And I don’t really have fresh air going into the room under the stairs, I open the door most the day but didn’t think that was good enough fresh air going into the room then going into the tent

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Where are you exhausting to? I feel like if you’re not circulating air you’ll have other problems. Like temp, and if you don’t have a temperature problem you may not have enough light. Can you give us a rundown on your setup?

My tent is 800mm x 800mm x 1.6m and is under my stairs in room that is 1.2m x 2.2m x 2.4m. I’ve got a 6in exhaust fan that takes the heat and smell into the lounge room which is 6m x 6m x 2.7m. So the only air I’m getting into the actual grow room is from the lounge. I was thinking that it’s not enough for the plants? Which is why i got the CO2 exhale bag.

In my tent is a mars eco 600w led, 6in circulating fan and a small fan heater that is pulled into a thermostat that turns on when the temperature drops below 23 degrees

Any feedback on my set up and advice with the CO2 bag is welcome.

And sorry about measurements! I’m in Australia and just what I’m used too haha

Have you used them before?

No. Just everything I’ve read about co2 usage. It’s said that you have to pretty much be drowning your plants in light. Say a 1000w hps in a 3x3 area. And you can’t use a exhaust fan or you’re just going to suck co2 out. You could use a gallon of warm sugar water and yeast for way cheaper and get same results

Just as long as you circulate the air, there is plenty of co2 for your plants. You will be fine. My tent is in my bedroom room. I don’t use c02, just the air in my house

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Standard Co2 levels in the atmosphere are approximately 450 PPM, so as long as there is fresh air coming in, and an exhaust out, your plants will get plenty of carbon dioxide. @RedcrabOz
Co2 does work, but you do have to have a lot of light for it to work effectively. As HornHead pointed out.


I have 2 bags in my 4x8x7 tent and it’s not sealed and during the day my C02 levels range from 800-1050 and that’s with the air exchange with my passive intakes and 8” in line fan.

My lights are enough to handle that level of C02 and up but at this time I’m not going to add C02 tanks etc to get it to the 1500ppm that could be used.

I haven’t tried the sugar water method …have you?

If you don’t use something is it fair to comment on it as being a waste of money and garbage? I try not to comment on things definitive like that unless I have had experience with it.

Just saying better to give no advice than advice from others that may or may not be valid.


I never mentioned that he should stop using the Co2 bag, I only stated to the original poster that they needed enough light for it to make a difference. @Skydiver


You’re right. I should have said in my opinion. I should have worded it better


I have used the sugar water yeast. I use 7 gallon pots so my plants are kinda high off ground. I can slide milk jug under plant right by pot. I think it worked pretty good although I didn’t have any thing to compare it to


To answer your question the best place is to put them low in the tent, Co2 is heavier than air and will come out of the bag and fall to the ground and your exhaust fan should be at the top of your tent, thus will suck the Co2 up thru your plants, yes it gets sucked out but on it’s way out your plants pick up some extra Co2. Put opposite of wall of your exhaust. There is a hole on top of bag and tie it upwards so the little vent stays open, I am for doing anything to make my girls happy , that will increase the swell and the frost on buds. ps(if you put above plants you exhaust will suck it out before the plants have a chance to get any) Good luck and happy growing !

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Correct me if I am wrong but I think I read somewhere that you only use co2 during vegg

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No, the Co2 supponsed to grow huge buds, some people spend money on tanks, gas, timers, because at night the stoma is closed, Co2 does nothing, so timers turn it off, plus to save money it only comes on periodically, but with the bags it is a one time deal, always emitting and lasts 6 months till it becomes all white, it is done. Now I am not saying it works, but I do it because personally I think extra Co2 helps. thumb


Thanks for the advice and help guys!

You’re close, it’s lights on as opposed to lights off.

I agree, doesn’t sound like any additional co2 is needed here. Keep airflow through the space via exhaust and passive intake and will be good.


Alright thanks for that, now I know for future grows :+1: