6 Best CO2 Generators/Burners for Grow Tents and Grow Rooms

CO2 generators or CO2 burners are devices that produce carbon dioxide (CO2), a key compound that plants use for photosynthesis.

CO2 generators work by burning fuels, usually natural gas or propane. The combustion process produces CO2 as a byproduct, which is then released into the growing environment. 

Higher levels of CO2 significantly boost plant growth by enhancing the rate of photosynthesis, thereby improving indoor plant productivity. However, CO2 generators are expensive and operate. They also require a constant supply of fuel. If not properly ventilated, high concentrations of CO2 are harmful to both plants and people.

When choosing a CO2 burner, consider the size of your grow area, the CO2 requirements of plants, safety features, and fuel type. The most important factor is to ensure the CO2 concentration remains within an optimal range (usually between 1000 and 1500 ppm) for plant growth.

1. Titan Controls Ares 4 – Carbon Dioxide (CO2) Generator LP – Best autopilot controller 

The Titan Control Ares 4 contains all the necessary parts for a quick installation. You can find an AC power supply, CO2 generator, gas hose, ceiling hook, hanging chain, regulator, and appropriate hose. 

This system works with the available liquid propane (LP) and natural gas (NG) models. The Titan Controls Ares 4 CO2 system generator is suitable for smaller and medium-sized grow rooms up to 15 x 15 feet. It provides four burners with 9,052 BTU (British thermal unit)/hour for LP and 11,068 BTU/hour for NG models. You can control the gas source due to dual redundant solenoids.

The Titan Controls CO2 generator uses a durable powder-coated chassis for a hydrophobic environment. The frame lasts for an extended period and cannot be damaged so soon. 

This CO2 generator also uses brass gas burners resisting rust and corrosion, so the overall construction is solid and reliable for optimal use for an extended period. The Titan Controls CO2 generator remains intact and sturdy regardless of the outer or inner conditions. 

This system also contains a built-in tip-over switch, crucial for defeating gas sources if the machine accidentally fails. It keeps safety standards optimal for users and indoor plants.

We rated the Titan Control Ares 4 at 4.5/5 as it doesn’t have calibration, and its monitor offers precise readings. It’s not good for the summer months as it produces heat. Its list price is expensive, but it matches its design. 

Pros: Energy-efficient to reduce costs, longer lifespan.

Cons: Requires ventilation for high heat output. 

2. VEVOR CO2 Burner, 8 Brass Burner CO2 Generator for Plant – Best built-in safety system 

The Vevor carbon dioxide generator uses liquid propane as fuel, providing optimal CO2 levels for healthy plant growth. It provides a higher output of 22352 BTU/h to keep the plants and grow rooms healthy. 

This generator eliminates open pilot flames as it features an automatic electronic ignition module. You don’t need a pilot light, as the generator offers built-in security. 

The Vevor CO2 burner also uses a solenoid valve to ensure the gas does not leak for safe and convenient operations and optimal use. The built-in safety valve and the top-over warning design add more safety for indoor growers. 

This product is ideal for hydroponics as it offers a galvanized powder-coated shell. The material prevents rust and corrosion. The 304 stainless steel plate also withstands high temperatures, using a copper tube for a longer lifespan and durability. 

The Vevor CO2 generator is energy-efficient as it uses 8 brass burners for a combustion reaction, making an efficient CO2 delivery for higher yields and healthy plant growth. 

Due to its versatility, the Vevor CO2 generator is ideal for hydroponics, grow rooms, grow tents, experimental fields, and greenhouses. It covers areas up to 3200 cubic feet. 

We rated the Vevor CO2 generator at 4.5/5 mostly for its security standards and ease of use. However, their customer service could be more reliable for help.

Pros: Solid construction, easy to install and use due to hardware 

Cons: Requires the controller to reduce higher heat output, package issues with missing parts 

3. AutoPilot APGN0400 CO2, 4 Burner, NG Generator, White – The most convenient generator 

The Autopilot APGN0400 CO2 generator/burner features powder-coated steel enclosures, resisting moisture discoloration and rust. It provides a longer lifespan and a reliable structure for trouble-free operations. 

This CO2 burner uses a built-in safety valve and solid-state electronic ignition module to create a spark to light the burners. The Autopilot carbon dioxide burner also provides a safety tip-over design to shut off the gas source if the generator accidentally tips and falls.

The Autopilot carbon dioxide generator also provides a dual-working system. It offers liquid propane and natural gas systems and high-altitude versions in all sizes. It covers smaller and medium-sized grow tents up to 15×15 feet. 

When the system fails, this carbon dioxide generator uses a shut-down warning with LED error indicator lights. You can completely turn it off and prevent major accidents in your grow rooms. 

However, to use all safety features conveniently, you must install the pilot lights regardless of the autopilot system.

Still, its installation is simple and quick, as the Autopilot carbon dioxide generator comes with the necessary hardware parts for installation, such as cables, hooks, power cords, etc., for effortless setup. 

We rated the Autopilot carbon dioxide burner at 4.5/5 mostly because it requires extra money for lights, and there are issues with customer service, as they are not always available for customers.

Pros: A double-working system for more convenience, quick setup, and ease of use 

Cons: Shipping issues, as the package might take longer to receive or come damaged

4. ARC-POWER Hydroponic CO2 Generator – The sturdiest model 

The ARC-POWER Hydroponic CO2 Generator is designed with eight brass LP propane burners, ensuring efficient and consistent carbon dioxide production, which is crucial for plant growth. 

This device has an auto shut-off pilot feature that adds to its safety profile, preventing accidents due to gas leaks. The ARC-POWER CO2 generator also provides a safe tip-over design to prevent major accidents if something goes wrong and eliminate the risk of explosions. 

One of the main advantages of this CO2 generator is its robust construction. The brass burners are durable and resistant to wear and tear, ensuring long-term service. 

Its installation process is also convenient since the carbon dioxide generator has all the necessary parts for an effortless setup. The package contains power cords, hooks, hoses, hanging chains, etc., ensuring a simple installation procedure. 

However, the ARC-POWER Hydroponic CO2 Generator has drawbacks. It operates on LP propane, which might be inconvenient for users without easy access to this fuel type. Another downside is the absence of a built-in CO2 sensor, meaning users need an additional device to monitor CO2 levels in the grow room.

We rated the ARC-POWER Hydroponic CO2 Generator at 4/5. It also comes with a higher price.

Pros: Solid construction ensures sturdiness and longer lifespan, consistent CO2 output covers all plants, auto-shutoff features for more safety 

Cons: Requires additional equipment without a built-in CO2 sensor, expensive  

5. LTL CO2 Generator 4/8/10/16 Burner – The most versatile generator 

The LTL CO2 generator offers flexible burner options, including 4, 6, 8, and 16 burners. Thus, the carbon dioxide burner fits small and medium-sized grow rooms and larger ones up to 5000 cubic feet. 

This generator is versatile for various gardening areas, such as greenhouses, grow rooms, and hydroponics, as it uses both natural gas and liquid propane sources. 

The LTL CO2 generator provides consistent and optimal CO2 output for plants, enhancing photosynthesis and increasing yields by up to 40-50%. The uniform distribution of CO2 levels covers all parts of the grow rooms. 

Made of durable and reliable materials, the LTL CO2 generator provides a longer lifespan for indoor growers, even after more extended applications. The robust design prevents any damage and keeps the structure intact for more robust use. 

Its safety features are also advanced, as the generator uses built-in safety systems with an outer tip-over design to prevent explosions and gas leakage if the generator accidentally tips over and falls. It also has a built-in check valve to ensure you always have enough CO2 and regulate it if the readings are too high. 

We rated this model of LTL CO2 at 4.5/5. The LTL CO2 burner is a higher-end model, so it is not affordable for all users, especially newbies. 

Pros: The built-in system includes safety features and a long lifespan due to a high-quality structure

Cons: Too pricey 

6. LTL CO2GEN 10 burner, natural gas, high altitude – Energy-efficient 

The LTL CO2GEN 10 Burner is powered by natural gas and is designed for greenhouses, grow tents, and hydroponic systems. It’s engineered to provide a constant and abundant supply of CO2.

It also operates on natural gas, making it economical over time. 

The device comes with ten burners, providing an ample supply of CO2 to enhance the growth of your plants. 

You can also choose between the high-altitude and low-altitude models if you cover more than 5,000 feet or less than 5,000 feet, so the CO2 burner is adjustable for your needs. 

This generator has pre-installed clean-burning brass burners, the correct hose, and regulators for a simple setup process. The hardware contains all the necessary parts for the installation as well. 

If this product accidentally trips or falls, the system uses a built-in safety tip-over switch, automatically turning the machine off. Its electronic ignition with dual redundant solenoid valves eliminates open pilot flames and prevents the explosion. 

This 10 Burner Generator features a variable output to activate or deactivate burners. The CO2 burner runs with 2 burners, 6 burners, or the full 10 burners.

Its optimal output of CO2 is 6 – 27 cubic feet per hour. 

However, the LTL CO2GEN 10 Burner can overkill small grow rooms, making it less cost-effective for those with limited space.

We rated this model at 4.5/5. It might be higher for newbies, so it’s not affordable for everyone. 

Pros: Security benefits to prevent accidents, solid for longer lifespan 

Cons: Strong heat output for plants 

How to Choose the Best CO2 Generator?

To choose the best CO2 generator, consider material durability, compatibility factor, type of valve & gauge, display & sensor, grow tent size, warranty & price. 

Material Durability: Durable materials ensure your CO2 generator can withstand constant use without breaking down. They also resist wear and tear, extending the lifespan of the generator. Steel, brass, and metal are generally more durable for indoor growers, so look for generators made of such materials. 

Compatibility: Compatibility refers to the CO2 generator’s ability to work in different environments (greenhouses, grow rooms, grow tents) and with various equipment types (regulators, hooks, powder cords, etc.). A compatible CO2 generator works with your existing growing setup without requiring extensive modifications. Look for a CO2 generator that operates seamlessly with your current equipment.

Type of Valve & Gauge: The valve and gauge on a CO2 generator control and monitor the flow of CO2. The right valve and gauge ensure optimal CO2 distribution, preventing over-saturation or under-supply. Select a generator with a precision flow valve and a clear, easy-to-read gauge.

Display & Sensor: A display shows the CO2 levels, and the sensor detects these levels in the environment. Accurate displays and sensors help you maintain the right CO2 concentration, optimizing plant growth. Select a CO2 generator with a digital display for precise readings and a responsive sensor for real-time monitoring.

Grow Tent Size: The size of your grow tent determines the amount of CO2 required. A generator that is too small won’t provide enough CO2, while a generator that is too large wastes gas and money. Match the generator’s CO2 output with your grow tent’s size. For instance, a 10×10-foot tent typically requires a generator with a 10-15 cubic feet per hour (CFH) capacity.

Warranty: A good warranty gives you peace of mind, knowing that the manufacturer will cover any defects. Meanwhile, the price should fit within your budget without compromising quality. Aim for a CO2 generator with at least a one-year warranty. Price-wise, consider the upfront cost and the long-term operating expenses.

Why do you need CO2 generators for indoor growing?

You need CO2 generators for indoor growing as it boosts photosynthesis. Indoor plants use CO2 during photosynthesis to produce glucose, which fuels their growth. A CO2 generator ensures a constant supply of CO2 for grow tent, promoting faster plant growth and higher yields.

Indoor growers can precisely control CO2 levels using generators, ensuring optimal conditions for various plant species.

Higher CO2 levels help plants withstand higher temperatures, enhancing their resilience.

You can use other methods to boost CO2 for grow tents, such as compressed CO2 tanks. These tanks store CO2 under pressure and release it as needed. Compared to CO2 generators, generators don’t need refill, but tanks are easy to use and provide precise control. Tanks are costly over time and pose safety risks if incorrectly handled, which is not the issue with the generators.

You can apply fermentation. The fermentation process involves using yeast to produce CO2. It’s a natural and inexpensive method, but it doesn’t offer precise control over CO2 levels as the CO2 generators and the production rate needs to be consistent.

Growing mushrooms in your grow tent also increases CO2 levels as they emit CO2 as a byproduct of their metabolism. However, this method introduces moisture compared to the CO2 generators. Mushroom methods also require careful management to avoid fungal contamination of other plants, while generators don’t pose cush a risk.

Introduce CO2 from outside air into the grow tent using a ventilation system with an exhaust fan to bring in outdoor air, and supplement this with a CO2 generator or tank to enhance the carbon dioxide levels. While this method is cost-effective, it’s not as practical as the CO2 generator is for large-scale operations or urban environments with low outdoor CO2 levels.

Why is a CO2 generator so expensive?

A CO2 generator is so expensive as it is often made from durable materials like stainless steel, withstanding high pressure and offering safety and stability. This kind of construction tends to be more expensive than simpler designs made from cheaper materials, such as plastic. 

CO2 generators often include advanced features like precision flow valves, digital displays, and responsive sensors. These technologies enhance the generator’s performance but also contribute to its cost.

While CO2 generators have a higher upfront cost than other methods of adding CO2 (like compressed CO2 tanks or DIY systems), they offer cost savings over time. For example, they eliminate the ongoing costs of refilling or replacing CO2 tanks. 

How does a CO2 generator work?

The CO2 generators work by burning either natural gas or propane. When these fuels combust, they produce CO2 as a byproduct. The generated CO2 is then released into the grow room or greenhouse, increasing the concentration of CO2 in the air.

How to set up a CO2 generator in a grow tent?

To set up a CO2 generator in a grow tent, select a generator suitable for your tent’s size and plants’ needs.

Install the generator in a location where it evenly distributes CO2. It’s recommended to place it above the plant canopy as CO2 is heavier than air and naturally falls onto the plants.

Connect your generator to a power source and its fuel supply (propane or natural gas).

Set up a CO2 monitor/controller to measure the CO2 levels in your tent and adjust the generator’s output accordingly. Aim for a CO2 concentration between 1000 and 1500 parts per million (ppm) for optimal plant growth.

Test your setup to ensure everything works correctly. Monitor the CO2 levels over a few days to ensure the generator maintains the right concentration.

How do you use a CO2 burner in a grow tent?

To use a CO2 burner in a grow tent, connect it to a fuel source and CO2 controller and make sure the growing environment is well-ventilated.

The burner works with either propane or natural gas, so ensure you have a proper fuel source.

Use a controller or monitor to read and measure the CO2 levels in your grow tent and control the burner’s output. 

Ensure your grow tent is well-ventilated. While plants need CO2, they also need fresh air for healthy growth.