How To Use CO2 For Grow Tent Growing

Using CO2 for grow tent and grow rooms is a more advanced technique that can lead to insane growth. But, this strategy isn't for everyone - there are other factors at play.

Not every grow tent or grow room needs CO2, or should even consider supplementing with it.

We are going to help you decide if it can help your particular grow, and then show you how to use CO2 for your grow tent.

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How To Use CO2 For Grow Tent Growing

Using CO2 for grow tent and grow rooms is a more advanced technique that can lead to insane growth. But, this strategy isn't for everyone - there are other factors at play.

Not every grow tent or grow room needs CO2, or should even consider supplementing with it.

We are going to help you decide if it can help your particular grow, and then show you how to use CO2 for your grow tent.

What is CO2, and should I use it for my grow tent?

How to hang a CO2 device in your tent

CO2, an abbreviation for carbon dioxide, is a beneficial gas that plants use in the process of photosynthesis.

By introducing extra CO2 for your grow tent, you can see huge spikes in growth rate.

Many experienced growers are well aware of this and utilize it to their advantage. However, this may be your first time hearing of a relationship between CO2 and plants.

Luckily, introducing additional CO2 into your garden is simple. But should you use it?

Read on to learn why you should be using CO2 producers, how to use them, and things to watch out for.

How does CO2 in the grow tent increase plant growth?

CO2 is essential to growth and development of all plant life.

The naturally occurring concentration of CO2 in the air is around 400ppm (parts-per-million). If you are growing outdoors, you will be limited in introducing additional CO2 to your plants.

However, growing indoors presents the opportunity to introduce extra CO2 to benefit of plants.

When you are able to raise the concentration of CO2 in the grow room to between 1,200-2,000ppm, you will see heavier yielding plants that develop much faster, and are heat resistant. But, there's a catch.

CO2 and your grow lights

The relationship between photosynthesis, CO2, and your grow lights

The main determining factor in whether or not you can benefit from supplementing your grow with CO2 is your lights.

If you are using higher intensity grow lights, such as HIDs, LEDs, or CMHs, you will benefit from CO2 supplemenation.

But, if your grow light is not powerful, and thus the "limiting factor" in your grow, adding CO2 won't do much.

T5's and CFL's are great for propagation, or supplemental lighting. On their own, however, they are not intense enough to benefit from additional CO2 supplementation.

Additional CO2 will only be as effective as your grow lights!

How to supplement your grow with CO2

Introducing extra CO2 to your indoor garden is not only incredibly beneficial for your plants, but also incredibly simple.

With the right preparation and an hour or two of free time, you can easily set up a system in your grow space to introduce supplemental CO2 at the right time and concentration.

There are several different methods of bringing in CO2:

CO2 Tank & Regulator kits - best for grow tent growing

The most common method of introducing extra CO2 to a grow space for home growers is a standard tank and regulator kit.

A CO2 tank, usually either 25 or 50 pounds and made of aluminum, is filled with compressed CO2 and can sit outside the grow tent to save space.

This tank is then hooked up to a regulator, which is then plugged into either the wall or a CO2 controller.

The regulator allows you to control the flow of CO2 as it is emitted from the tank. This helps ensure that enough CO2 is being released to have a beneficial effect on the plants, while preventing excess from leaking.

The CO2 is then emitted through tubing that is hung throughout the entire grow tent, above the canopy of the plants so that it can descend down upon the plants as it is released. If you are growing in a tent, using a tank will be your best option.

CO2 Burners - best for grow rooms

Not as common as using a tank, but still a very popular option, is creating extra CO2 in the garden using a CO2 burner.

When liquid propane (LP) or natural gasses (NG) are ignited, they produce CO2 as a result.

The burner consists of as few as two, or as many as ten burners. These are housed in a metal box that is hung from the ceiling of the grow room above the canopy of the plants.

A tank of either liquid propane, or a natural gas is then hooked up to the regulator, which is then plugged into a CO2 controller.

As the gas is released into the generator, the burners ignite it and CO2 is produced. It then descends down onto the plants.

This process can introduce a good deal of heat to the grow room, as it relies on combustion to function.

This is important to consider if you are growing in a small tent or an area prone to high temperatures.

You may find yourself constantly fighting to keep your grow room temperature at an ideal level, and will need a grow room air conditioner.

Natural CO2 Methods

There are numerous ways of creating extra CO2 in your garden naturally.

We carry many natural CO2 methods that can help you take advantage of this method without using much space or a big investment.

From bags containing CO2 producing fungi to pads that are hung above the canopy of your plants and react chemically to the humidity present in the room to release CO2.

Naturally producing CO2 is a quick and inexpensive option that can serve as a helpful backup plan if you run out of CO2 in your tank unexpectedly or if your generator stops working.

However, we do not recommend using natural methods as the primary way of introducing extra CO2 to your garden.

These are less efficient, and more difficult to regulate as they can not be shut off by a CO2 controller.

CO2 Controllers

Just as important as your method of bringing in CO2, is the method of controlling it.

Programming CO2 controller

If CO2 is not controlled it will release too much, which can be detrimental or even fatal for the plants.

Another common issue is releasing CO2 at the wrong times. This will waste a valuable resource as well as your money.

A CO2 controller serves the purpose of monitoring the total concentration of available CO2 present in the grow room’s air.

If necessary, it will shut off any connected CO2 producing devices when the ideal level is reached.

Once the concentration has depleted, the controller will turn the CO2 device back on.

These controllers are also equipped with photocell, which allow them to determine if it is day or night time. A controller with photocell will keep CO2 devices on the same schedule as grow lights.

This is critical, as CO2 only needs to be present for the plants during their daylight hours as that is when photosynthesis occurs.

Releasing additional CO2 during the period of the day where the lights are off in the grow room is a complete waste.

More information on using CO2 in your grow tent or room

While knowing how to introduce the additional CO2 to your garden is important, knowing how to properly setup your garden for the high concentration of CO2, and when exactly to utilize it is just as important.

Closed loop grow rooms & CO2

CO2 supplementation should be be avoided unless the grow room or tent is completely sealed, or a "closed loop"w. Many indoor growers choose to run an inline fan 24/7 in their garden to help control heat and humidity.

This unfortunately will not work if CO2 is going to be added to the room. The fan will exhaust the majority of the CO2 before it could have any effect on the plant’s development. Instead, the room should be set up as a “closed loop”.

A closed loop room does not run a continuous exhaust fan as an open loop room does. Instead, this type of room only utilizes the exhaust fan when temperatures, humidity, or CO2 rise to an unsafe level.

When supplementing CO2 for your grow tent, you need a closed loop environment

As you can see in the illustration, the closed loop room is completely sealed. There is no exhausting of the air within the room to outside of it. Instead, the inline fan is merely used to help control odor and circulate air.

You can read more about the differences between closed/open loop rooms, and ventilation systems in our article about Grow Room Atmosphere and Ventilation.

CO2 Safety and Precautions In The Grow Room

Being exposed to high levels of CO2 can have fatal results. If the equipment used to produce CO2 in your garden is setup correctly, with the room properly sealed, there is nothing to worry about.

But it always a good idea to be prepared for the worst case scenario.

CO2 is a completely odorless and colorless gas, so it is unlikely you will recognize its presence in time.

It is wise to invest in a CO2 detector or alarm that can be plugged into any home outlet. Install this outside of the grow room, of course, and it will alert you of any issues.

Parting Thoughts On Adding CO2 To Your Room Or Tent

If your goal is harvesting huge plants with a heavy yield, you should be supplementing with CO2.

With the right grow light system, CO2 supplemeation can supercharge your growth like you've never seen before.

If you want to use CO2 in your garden, but are having trouble choosing a system, reach out to us!

You can call us at 888-815-9763 and speak with any of our experienced professionals about CO2. We are happy to discuss any other aspects of gardening as well!

Want to learn more about creating the best environment possible for your plants? Check out our other articles in this learning center.

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