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How CO2 affects your plant and the growth

If plants require CO2, then it makes sense that increasing levels of CO2 will positively affect your plants growth, with studies showing 20-30% better results if the CO2 is utilized 100%.


Before actively raising the levels of CO2 into your grow space there are a few things you need to consider. During this blog post we will discuss the advantages and disadvantages of implementing CO2 into your grow space.


Things need to know before implement CO2 into grow space 

As mentioned above, you will expect to see 20-30% better results if your CO2 is 100% utilized. However, there are some things to know before attempting to get these kinds of numbers. 

Having more lights in the grow space

When you start supplementing CO2 your plants will be able to use more light. You will need to ensure you are able to give the plants that extra light or the plants will be bottlenecked. In addition, as you increase the light levels and CO2, you will expect to have higher temps also.

Best co2 level for plant growth

Studies show the optimum CO2 level for your plants to work at peak efficiency is 1200ppm. This level is typically used in a "closed loop" setting. Meaning you are not running an exhaust fan inside of your growing system as there is no need to. This comes with its own complications such as a decreased ability to control the temperature

2000+ ppm CO2 level is toxic to human

While levels of 2000+ ppm are considered toxic to humans, it is not recommended to be in an area that is at 1200+ as long exposure to these levels can have adverse health effects.

How to supplement CO2 into the grow space? 

Pressurized injection


The best way to supplement CO2 into your grow space is by pressurized injection. Injecting CO2 is quite a 'step in the deep end' as the setup for this is not recommended for beginners. 

Pressurized CO2 injection system

A pressurized CO2 injection system will consist of a cylinder of CO2 that is under pressure with a regulator screwed onto the top which allows you to control the rate that the CO2 flows out. A lot of pressurized injected systems will have an electric solenoid to electrically control the flow of the CO2, a needle valve which enables to make very fine adjustments to the flow rate of the CO2 and a bubble counter to give a visual on what your flow rate is doing. It is recommended to use mineral or vegetable oil in your bubble counter as water will eventually evaporate.

Using mushrooms


A simpler way but not as effective is the use of mushrooms. Unlike plants, fungi are similar to humans, they breathe in oxygen and release CO2. This makes them a good companion in your grow space. 


It is common to find bags of substrate that have been inoculated with a fungus. As these fungi colonizes the substrate there will be a gas exchange port to enable the CO2 to leak out. This can be used by your plants in almost like a symbiosis relationship. Using CO2 bags is a much more beginner friendly way to supplement CO2 into your grow space while still seeing decent results. Keep an eye out on our website for a bag like this soon.