THE IMPORTANCE OF ADDING CO2
TO YOUR GROW ROOM

Indoor gardeners are always looking for new and innovative ways to boost their yields. There is, in fact, a very simple way to maximise your yields and grow strong and healthy plants, and this is by adding CO2 to your grow room. But what exactly is CO2, what is the best way to add CO2 to your grow room, what is the best CO2 system, where can you find the best CO2 bags for grow rooms, and how does it benefit your plants?
What is CO2?
CO2, or carbon dioxide is what we expel when breathing, and what plants use to initiate photosynthetic functions. Plants actually ‘breathe in’ CO2 in the day, but give out CO2 at night. Levels of CO2 are measured in PPM (parts per million), and ambient room levels are typically in the region of 300-400ppm. Assuming you have sufficient circulation in your grow room you should be able to achieve the atmospheric standard of 390 PPM. At this level, you should see plant growth similar to what you see in your garden.
If the CO2 levels drop below 200 PPM, your plants will stop growing.
It is understanding this behaviour that can really benefit your grow. If everything is being done correctly and you have a fine tuned system, then CO2 can be the one big difference in boosting your yields. Adding enhanced CO2 levels to your grow can significantly boost plant growth without having to change the way you grow.
If you are looking to accelerate the grow cycles of your crops consider adding additional CO2 to your grow room. Plant growth accelerates as you increase CO2 levels up to around 1,500 PPM. Growers have observed up to a 100% increase in grow speed at 1,500 PPM.

The Benefits of Adding CO2 to your Grow Room
The most important and obvious benefit to your plants is the significant increase in growth that will occur, especially if the potential of your set up has already been maximised.
In addition to this, if levels of CO2 can be maintained around 1000-1200ppm then you will be able to run your grow room at a higher temperature. This can be incredibly important with growers constantly struggling to keep temperatures down and avoid temperature stress to your plants. The best CO2 system to add to your grow room should be an organic solution with no maintenance and no running cost..
CO2 During Vegetation
During the vegetative growing stage adding CO2 is the biggest way you can increase the rate your plants stretch, allowing your plant to grow with a lot more vegetative grow in a much shorter space of time.
CO2 During Flowering
When adding CO2 to your grow room, the flowering stage is the most important. Adding CO2 to your grow room, especially in the first 2-3 weeks of flowering, can kick start flower production and boost flower size significantly.
How to Add CO2 to your Grow Room
Using exhale CO2 bags are the natural and easiest way of adding CO2 to your grow room. The Exhale CO2 bag cultivates carbon dioxide 24 hours a day with no need to refill bottles or use expensive production units.
They work through photosynthesis – photosynthesis is the process by which plant leafs make carbohydrates. Sunlight, carbon dioxide and water are converted into carbohydrates and oxygen by the action of chlorophyll in the chloroplasts of the plant. Plants growing indoors under artificial light often lack enough CO2 to efficiently photo-synthesise. When plants are able to maximise the process of photosynthesis, the result is larger plants with larger yields.
The power lies in the mycelial mass inside the vented cultivator. This mycelial mass cultivates carbon dioxide and the one-way breather patch releases CO2 continually for up to 6 months.
Please note, that as CO2 is heavier than air, the exhale CO2 bag should be hung at the top of the grow room to deliver a shower of CO2 over your plants.
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I am starting a grow in a tent, and its also in my room would it be safe to add c02 and how much would be if any
Hi Andrew, yes it would be safe to add to your tent. Hanging an Exhale CO2 bag would be the best way to achieve this.
With cost savings in mind and a larger then average greenhouse. Why not burn a small amount of pellets or wood shavings. This is what a plant does outdoors(filter smoke+commercial gasses. Misting the leaves with water to refresh the surface and reintroducing CO2 + more helpful gases via smoke. Any input?
Hi, that’s an interesting concept and one we’ve not come across before. Personally we would use the Exhale CO2 bag to naturally add the CO2 to your greenhouse rather than filling the place with smoke.
I thought CO2 was dangerous for humans so how is it controlled so that one can work in the room without keeling over ?
Hi Audrey, while the CO2 bags will raise levels sufficiently for plants, there will be no toxic effect to humans at the levels given out.
I have a 4 foot by 9 foot by 7 foot grow tent how many bags would I need and how often would I need to change them out
It takes levels around 5000 parts per million to become deadly. Naturally occurring CO2 in the air outside has about 400 ppm. Ideal growing range is 900-1200 ppm
Do I need a diffuser like in an aquarium if using tank regulator method
I use an exhale co2 bag in my 2×4 grow tent, its in my living room, not a problem at all.
We have sealed rooms. No outside air unless the door is open. Right now we are piping in C02 but cannot get the levels consistent. Could switching to the bags help?
Absoultely, not only would they help the situation but the CO2 bags will also save you money!
Use a CO2 regulator, appropriate sized CO2 tank for your growing area, and set the pre-drilled tubing up on the ceiling so that it is covering your entire garden. CO2 is heavier than air so it will sink. Also, place your CO2 probe that comes with the regulator directly in the center of your garden just above the current canopy height. Good luck and happy growing everybody!
If I used like a “Laundry Line” type system to hang these over my outdoor grow, Theoretically it’d work, yes?
HI Anthony, yes this would work and has been known to be done in the past.
Is it ok to leave the exhale bag open while in darkness?
Hi James, yes it’s absolutely fine to leave the Exhale bag open in darkness. Once you move the hanger above the filter patch the bag will safely produce CO2 for 6 months.
Without a co2 regulator how does one know how much co2 they have added? Say I put one bag in and get good results, can I add another how many is just right? (4×4 tent)
Hello Marc, If you’re looking to accelerate the grow cycles of your crops increase CO2 levels up to around 1,500 PPM. We would recommend getting a CO2 monitor to measure the levels in the grow space and then add more bags if necessary, but 1 bag should suffice for this area.
How long do o use c02 tank for in flower ?
How long would one of these bags last me? Great concept btw!
Hi Johnny, the standard Exhale bag will last 6 months. The Exhale 365 will last a whole year!
Hello,
I have a relatively small grow tent. About 3 plants at the moment. (80x80x120) Would this be something I could use?
My plants are in flower and they have been growing just fine. I am interested in accelerating growth.
Warm Regards
Yes you certainly can use our Exhale CO2 bags to give your plant growth a big boost.
will co2 introduction alone increase the temperature in my greenhouse or will i have to manually add extra heat
Hi, Co2 introduction will not increase the temp significantly and you would need to manually add extra heat.
Will the co2 bag still work in a vented grow room
Thanks for all the input. Very helpful. Keep up the good work.
Can i use the bag in the 6th week of flower
Hi yes you can use during all stages of flower
If earth’s ambient temperatures rise with co2 levels, why would grow room temperatures not rise commensurately with the addition of co2 using your Exhale co2 Bags? Are there other factors that affect grow room temperatures?
The warming of global temperatures is caused by CO2 being trapped in the atmosphere,
where as the CO2 in your grow room is utilized by your plants through the process of
photosynthesis and creates oxygen which does not lead to a temperature rise.
Should you just use the co2 in the day while the plants breath or out during the night?
And how long would you have it turn on for? All day or constantly after the flowering has started?
In answer to your questions, the ExHale strain is light sensitive meaning the majority of the CO2 production takes place when the lights are on. During the night cycle the bag dramatically reduces CO2 production until the light cycle begins and the CO2 production increases again. And we suggest using ExHale for both vegetative and flowering phases.
If my tent is vented with fan and filter, will i still be able to acheive 1500 ppm?
On average our bags will raise the ppm in a given space by 500ppm above ambient. With regard to ventilation, we suggest placing the bag down low, close to the fresh air intake. CO2 will be drawn up through the canopy and utilized by the stomata on the leaves before being exhausted.
Good day…
Would injecting Co2 into the root medium (soil/hydro) help?
No, roots need Oxygen.
l believe you are thinking about mycorrhizae, which are soil inhabiting fungi that support and stimulate plant growth. ExHale produces CO2, which is an air additive that boosts photosynthesis and increases plant yields.
Why do I need to raise temperature with a co2 bag? Can I leave the temperature as it is? It’s already at 85 degrees fereinheit during light time. I can’t risk raising the temperature. Its 100 degrees outside everyday, very hot summer right now. I’m in week 4 of bloom. I want a co2 bag. Any advice? Does the bag go under the lights or above the lights?
You do not need to raise or lower the temperature of your grow space to use ExHale. The ExHale strain is tolerant to a wide range of temperatures. It is noted that plants with added CO2 can better withstand hot periods of time like you mentioned. As far as a placement, above or below the light is fine.
If I hang a co2 bag in my tent
Will the filter suck it all away
If you are running ventilation, we suggest placing the bag down low, close to the fresh air intake. CO2 will be drawn up through the canopy and utilized by the stomata on the leaves before being exhausted.
I want to control the CO2 levels in an artificial environment, could I use one of these bags and an adjustable valve to limit the CO2 levels in the environment? (I would be using a computer to measure the CO2 levels and automatically adjust the ppm to maintain a specific value)
Our bags are designed for specific size areas. Our original size bag is designed for a 1.2m X 1.2m space and our XL size bag is designed for a 1.8m X 1.8m space. Bigger space, simply add more bags. Each bag in the given space will raise the CO2 level on average 500ppm above ambient. You can control your levels by adding more or removing some bags.
Hi should l leave the fans on when l put the bags in my grow tent?
Thanks
Yes, you can leave your fans on. With fans and ventilation, we suggest placing the bag down low, close to the fresh air intake. CO2 will be drawn up through the canopy and utilized by the stomata on the leaves before being exhausted.
Hey there, if I raise the heat and wattage of my lights in a well trained s.c.r.og tent setup is there benefit to going beyond 1500ppm say to 2000 or 3000 or does it simply plateu at 1500
Going above 1500ppm is really not necessary. Plants can only utilize so much CO2 through the process of photosynthesis. If needed because of the summer season, higher CO2 levels will allow a plant to withstand higher temperatures. Growers using ExHale see, on average a 20-30% increase in yield.
Is having co2 ppm over 1500 beneficial
Going above 1500ppm is really not necessary. Plants can only utilize so much CO2 through the process of photosynthesis. If needed because of the summer season, higher CO2 levels will allow a plant to withstand higher temperatures. Growers using ExHale see, on average a 20-30% increase in yield.
Hi ,
Do you have to turn extraction off for best results ? ..
Or would having the extractor on a timer to turn on /off at intervals.. tia gagaz
With regard to ventilation and extraction, you can leave the fans on. We suggest placing the bag down low, close to the fresh air intake. CO2 will be drawn up through the canopy and utilised by the stomata on the leaves before being exhausted.
I have the inline carbon filter in my grow tent… by adding a co2 generator… would they counter act eachother?
With regard to ventilation, we suggest placing the bag down low, close to the fresh air intake. CO2 will be drawn up through the canopy and utilized by the stomata on the leaves before being exhausted.
I have a twelve by twelve sized room is this grow bag safe to use if I don’t quite have ventilation set up yet?
Yes the CO2 grow bag is perfectly safe for use!
If I am filtering the air will I need to turn the ventilation system off?
With regard to ventilation and extraction, you can leave the fans on. We suggest placing the bag down low, close to the fresh air intake. CO2 will be drawn up through the canopy and utilised by the stomata on the leaves before being exhausted.
I ordered a exhale CO2 bag. I have a 5×5 tent. Should I remove the bag at night when my lights shut off or is it ok to leave it in tent 27/7
Hi sorry for the late reply, you can leave the exhale CO2 bag in overnight no problem
hi,
i saw you comment about putting the c02 bag near the fresh air intake. Is it a problem if the bag doesn´t get direct light from the lamps?
Hi Patrick, no our Exhale CO2 bags do not need direct light from the lamps and will work fine
I have a small grow tent – 2-feet by 2-feet by 5 feet tall. (Oops! Since this site is in UK, it’s about .6-meters by .6-meters, by 1.5 meters tall!!) The grow tent will be closed, but, of course, an outside fan for the intake, and a fan inside the tent to circulate the air. This is a room I spend a lot of time in, with my computer and classical guitar. Do I need a CO2 meter, or do I not need to worry?