In the near future, the United States prohibition on cannabis for medicinal and recreational use is going to end. Home growers are coming ‘out of the closet’ all over the country as weed is legalized, decriminalized and regulated in state after state. As a grower, you have complete control over your crop from seed to harvest. You get to choose your strain, whether you grow indoor or outdoor, what kind of hydroponic equipment to use if you are an indoor grower, and with automated equipment you can even decide how much work you put in to the crop on a day to day basis.
But as they say, with freedom comes responsibility, and as a new cannabis cultivator it is in your best interest to learn as much as you can about the plants you are growing in order to increase your yields as well as the medicinal properties of your harvest. Carbon Dioxide, or CO2 is of particular interest to cannabis gardeners. CO2 is crucial to marijuana cultivation, because it is what plants “breathe.” Humans and plants live in a symbiotic relationship – we breathe in oxygen and exhale CO2, while plants consume CO2 and release oxygen into the air.
Right now, the parts per million (PPM) of CO2 in Earth’s atmosphere are 350. Scientists believe that millions of years ago, CO2 levels were much higher at 1,500 PPM. What does this mean for cannabis growers? All plants, cannabis included, still have the ability to utilize up to 1,500 PPM of CO2, and the more they are given, the bigger they grow. The same is true for low levels of CO2 – if you do not have proper ventilation in your grow room, your plants will use up all of the CO2 in a few hours. They will essentially suffocate, their growth will be stunted and they may even die. If you are able to increase your grow room’s CO2 levels, this means you will have healthier, happier plants that will give you greater yields of buds from the same number of plants. You can easily increase your yields by 20 to 30 percent by supplementing with CO2.
This is where CO2 generators come in. CO2 generators release controlled amounts of carbon dioxide gas into your grow room for your plants to consume. It is essential to have a controlled release, because levels of over 1,500 PPM are toxic to cannabis plants.
CO2 generators come in three parts: a regulator, a controller, and a tank. The tank holds the CO2, the regulator controls the release of CO2 from the tank, and the controller is a piece of electronic equipment that you can program for a precise release of just the right amount of gas per hour. You can purchase these parts separately, or in an all-in-one package. An alternate solution for growers with less cash to spend is a CO2 bag, bucket or mushroom kit. We will get into all the details below. If you’re starting a cannabis grow op for the very first time, you may also find our guide on how to grow cannabis very helpful. And of course, always make sure you follow all local laws and regulations when purchasing the following materials.
Inexpensive CO2 Options for Beginners
1. MyCO2 Air Bloom/Grow Box
If you want to boost your CO2 without having to invest in an expensive CO2 generator, the options in this section are a great middle ground. MyCO2 Air boxes use mushrooms to release either a rapid, or a slow release of CO2 in your grow room. The “Grow” box uses reishi mushrooms to slowly release carbon dioxide over the course of a few months,to supplement your plants growth in the vegetative state. The “Bloom” box uses blue oyster mushrooms for a more rapid release of CO2 curing the flowering period. Each box is sized for a 4×4 grow tent (with proper ventilation), so you can purchase more if needed for a larger grow op.
Buy the “Grow” slow release box here, or the Buy the “Bloom” fast release box here
- Very inexpensive
- All natural with no extra equipment needed
- Comes in two sizes for veg and flowering states
- Not very powerful for larger grow ops
- Some reviewers did not like the results
- Doesn’t put out as much CO2 as more high tech set ups
Find more MyCO2 information and reviews here.
2. ExHale CO2 Bag
ExHale’s CO2 bag is another hassle-free CO2 solution that requires no equipment and no electricity to use. The bag is a vented mycelium cultivator that releases CO2 into your grow room in a continuous stream over a span of six months. The bag comes in two sizes – original or XL. The original size is designed for small or medium sized grow tents around 4×4 feet. The XL size can provide CO2 for a space about twice that size at 36 square feet. This system can be used for both vegetative and flowering phases of life.
Price: $33.95 for the original, $52.95 with free shipping for XL.
Buy the original size ExHale CO2 bag here, or the ExHale XL size here
- Very easy to use
- Maintenance free
- No electricity required
- Uses plastic with BPA, pthalates, etc.
- Only lasts for six months
- Does not put out as much CO2 as professional quality emitters ag
Find more ExHale information and reviews here.
3. ProCO2 Bucket
The ProCO2 bucket uses the same basic principles as the previous two options. It releases CO2 in a steady stream 24 hours a day into your grow room over the course of about three months, which with the right ventilation equals a boost in CO2 levels for your plants. The bucket comes with a built in air pump and is suitable for an area of 8′ x 8′.
Price: $48.95 with free shipping
Buy the original size ProCO2 bucket here, or the ProCO2 XL size here
- The original model is the least expensive option available for CO2 emitters
- Comes in two sizes for different sized grow ops
- Maintenance free, just set it up and go!
- Some reviewers recorded a relatively low CO2 output
- Bucket is heavier than other low-tech options
- Does not include equipment for hanging bucket
Find more ProCO2 information and reviews here.
Professional Quality Automatic CO2 Regulators
When you have a large grow room or you want to grow professional-level weed, you need a fully automatic CO2 generator. CO2 bags and buckets just won’t cut it if you have a grow op with a significant number of plants, or if it is larger than 10×10 feet. Even if you have a small grow op and want to increase your yields significantly, automated CO2 regulators provide a way to maintain optimal CO2 levels worry-free so you don’t have to manually measure and change output levels.
The easiest option for professional growers is to buy an all-in-one system that includes all of these elements. This reduces the time spent setting it up and guarantees that all components will work together seamlessly. Usually these all-in-one systems use a series of gas burners to emit CO2, instead of a pressurized tank. Here are the top systems, ready to be installed and start using right away.
1. Hydrofarm Autopilot CO2 Generator
Hydrofarm’s Autopilot system is incredibly safe and reliable. This system works by burning propane or natural gas, and is available in high or low altitude models as well. It is constructed inside of a powder-coated steel enclosure to resist rust in humid grow room environments, and features a two stage pilot light that prevents fuel flow unless the burner is lit. This means that if the unit falls or tips over or if the flame is disturbed, the fuel will immediately shut off. It is super easy to set up and operate, as well. All you need to purchase in order to start running this system is the propane tank, or hook it up to your gas line if you choose the natural gas option.
Price: $331.45 with free shipping
Buy the Propane option with 4 burners here, the Propane option with 8 burners here, or the Natural Gas option with 8 burners here.
- Very effective at delivering high levels of CO2
- Comes in a variety of sizes for different sized grow rooms
- Can be used with either propane or natural gas
- You can choose a high- or low-altitude model
- Requires buying and storing fuel
- May pose a fire hazard if not monitored properly
- Requires assembly
Find more Hydrofarm Autopilot information and reviews here.
2. Titan Controls Ares CO2 Generator
The Ares CO2 Generator from Titan Controls is another top of the line option for professional growers. It uses either propane or natural gas to create CO2 and are very easy to set up and operate. the system comes ready with everything you need to get started right away. It also has built in safety features to prevent gas from flowing when the system gets knocked over or jostled, so you don’t have to worry about gas leaks in your grow room. You can choose from a number of options, with units as little as two burners or as large as ten burners, and natural gas or propane for each size.
Price: $260.23 to $446.12 with free shipping, depending on what size and style you choose.
Buy the Titan Controls Ares CO2 Generator here
- Comes in propane or natural gas options
- Extremely efficient
- Customizable for different grow ops sizes
- More expensive than other options
- Does not come with warranty
- Does not come with hanging equipment
Find more Titan Controls Ares information and reviews here.
DIY CO2 Controllers
If you want something a bit less expensive, you can purchase the components for a CO2 generator separately and put them together at your leisure. This gives you more control over the system. You can choose equipment that meets your budget and the size of your particular grow op. However, just because your system is DIY does not mean it has to be cheap, because you can purchase all of the top of the line equipment and piece it together yourself. If you are experienced or do your research well enough, you can even put together a system that beats pre-made options in terms of output, efficiency and yield enhancement. One of the benefits of DIY CO2 generators is that they do not require the use of fuel such as propane or natural gas, and they do not require a flame. This makes them a more safe option if you plan on putting your system on autopilot. Here are some options for the three components you need in order to set up a DIY system.
- Luxfer CO2 Tank: Luxfer tanks are 20lbs and sell for $146.11 with free shipping.
- Hydrofarm CO2 Tank: For larger grow ops, Hydrofarm has a 50lb tank for $410 with free shipping.
- Pro Co2 Regulator: This regulator costs $60 with free shipping and is made from mainly brass components. It has extremely high reviews on Amazon.com from customers who say it works great.
- Titan Controls: Titan Controls also makes a regulator for $84 with free shipping that will fit right in with their CO2 tank. It is also perfectly compatible with their CO2 controller or any other 120V controller.
- VIVOSUN: At $45, this is a less expensive option than the others but it does not skimp on quality. Components are still mainly brass and it has a pressure gauge and solenoid valve.
CO2 System Controller:
- Titan Controls Atlas 2: This controller is an excellent choice for grow ops of any size, and fits seamlessly with other Titan Controls products. It costs $232 with free shipping. It is super easy to use with settings from 1,000 PPM to 2,500 PPM, but is preset to 1,500 PPM.
- Titan Controls Saturn 5: Titan Controls also makes a CO2 controller that costs $197 with free shipping. It regulates temperature and humidity as well by plugging in to your ventilation system. This one costs less at $190 with free shipping.
- AutoPilot Digital Environmental Controller: Costing $174 with free shipping, this controller dos exactly what the name suggests – it lets you put your entire grow operation on autopilot. It combines temperature, humidity and CO2 controls and has easy to read LED light signals to let you know if there is an error anywhere in your system. You can even differentiate you day and night controls from each other.