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8 Best CO2 Systems for Small Aquariums – 2022 Reviews & Top Picks

Sarah Psaradelis

By Sarah Psaradelis

Yagote CO2 Aquarium SupplyFinding a good CO2 system that can be incorporated into a small aquarium can be difficult, but there are some really good ones out there! CO2 (otherwise known as carbon dioxide) systems are great for helping plants grow fast and healthy, while still maintaining a good balance in your aquarium. All types of aquatic live plants benefit from carbon dioxide, whether it’s a lowlight or highlight plant.

Using CO2 systems in an aquarium falls into the high-tech plant aspect because it uses external equipment to add in beneficial growth sources that may be lacking in the typical home aquarium. The majority of CO2 systems are easy to use and can look attractive in an aquarium if placed right.

If you are looking for the best CO2 system for your aquarium, then this article has it covered. We will review some of the top-quality CO2 systems to help your planted tank run smoothly while keeping the products affordable and attractive to fit into nearly every type of aquarium.

aquarium plant dividerA Quick Comparison of Our Favorites of 2022

Rating Image Product Details
Best Overall
Winner
VIVOSUN Hydroponics CO2 Regulator Emitter System VIVOSUN Hydroponics CO2 Regulator Emitter System
  • Durable and high-quality material
  • Accelerates plant growth by up to 40%
  • Helps maintain ideal CO2 levels
  • Best Value
    Second place
    Decdeal Aquarium DIY CO2 Generator System Kit Decdeal Aquarium DIY CO2 Generator System Kit
  • Safety measures in place
  • Quiet
  • Affordable and efficient
  • Premium Choice
    Third place
    SunGrow DIY Pressurized CO2 System SunGrow DIY Pressurized CO2 System
  • High-quality materials
  • Allows control over the amount of CO2
  • Cost-effective and sustainable
  • JARDLI Pollen Glass CO2 Diffuser with Bubble Counter JARDLI Pollen Glass CO2 Diffuser with Bubble Counter
  • Visually attractive
  • Designed for small tanks
  • Blends into environment
  • JARDLI Glass Inline CO2 Atomizer Diffuser JARDLI Glass Inline CO2 Atomizer Diffuser
  • Enhances CO2 dissolution
  • Inline mounting reduces algae growth
  • Mist increases absorption
  • The 8 Best CO2 Systems for Small Aquariums Are:

    1. VIVOSUN Hydroponics CO2 Regulator Emitter System – Best Overall

    VIVOSUN Hydroponics CO2 Regulator Emitter System

    Check Price on Chewy
    Type Regulator emitter system
    Power 110V
    Hose tail 4.2 mm
    Product dimensions 9.06 × 6.81 × 5.98 inches

    Out of all the CO2 systems available for small aquariums on the market, the VIVOSUN is the best overall. It is small and durable which makes it able to fit into nano aquariums and it does its job well. The material is made of long-lasting durable brass components which can function for years with little to no rusting. The application works well for enhancing the amount of carbon dioxide available to accelerate plant growth by up to 40% in hydroponic systems and planted aquariums.

    The kit includes a precision regulator, flow gauge, industrial solenoid valve, and a decent tubing length of 5 meters. The outlet source is suited for a USA standard 3-prong plug. This CO2 regulator allows you to maintain an ideal level of CO2 in your planted aquarium for optimal plant growth and development. It also looks attractive and is affordable, which makes it a good option for beginners who are starting in using CO2 systems, while remaining good enough for the professionals.

    Pros
    • Durable and high-quality material
    • Accelerates plant growth by up to 40%
    • Helps maintain ideal CO2 levels
    Cons
    • The metal is prone to rusting after a few years
    • Regulator may leak

    2. Decdeal Aquarium DIY CO2 Generator System Kit – Best Value

    Decdeal Aquarium DIY CO2 Generator System

    Type Generator system
    Power 12V
    Hose tail Not specified
    Product dimensions 8.66 × 4.8 × 2.83 inches

    The Decdeal CO2 System Kit is known for its best value for the money. This kit includes everything you need to get started on a good CO2 system for smaller aquariums with minimal hassle. The system has been manufactured with a high-quality aluminum alloy which makes it strong and durable with well-sealed caps and pipes to avoid leakage. It includes a professional pressure gauge so that you can easily monitor the pressure. It is affordable and simple to create a pure CO2 system that runs constantly through chemical reactions.

    The system runs quieter than other solenoid systems and the flow rate of CO2 gas exchange is an indication device to prevent water from flowing back into the bottle. It is completely waterproof which helps to prevent any electrical currents from harming you and your aquarium. It is safe and can be manually relieved by pulling the safety ring valve in the case of an emergency.

    Pros
    • Safety measures in place
    • Quiet
    • Affordable and efficient
    Cons
    • It May be complicated for beginners to setup
    • Requires plastic bottles for final setup

    3. SunGrow DIY Pressurized CO2 System – Premium Choice

    DIY Pressurized CO2 System

    Type Pressurized CO2 system
    Power 12V
    Hose tail Not specified
    Product dimensions 8.03 × 5.98 × 2.13 inches

    Our premium choice is the SunGrow DIY CO2 System which includes all the equipment needed to start your very own CO2 system that can be tailored towards the needs of your aquarium. To build a good CO2 system, this product offers everything you require, such as two caps that fit on standard PET plastic bottles, a needle valve, check valve, pressure gauge, a 3-way connector, and a long piece of tubing which is a reaction material that connects it to the diffusor. This CO2 system adds much-needed gases that aids in proper plant growth to produce healthy plants. It saves you money from having to find the right-sized CO2 system for small aquariums by allowing you to complete the setup using your desired materials that can be found in your own home.

    The material is of high quality which makes it durable and long-lasting. Personal adjustments can be made to ensure that it works perfectly for your aquarium and helps to avoid any negative effects on your plants and aquarium inhabitants.

    Pros
    • High-quality materials
    • Allows control over the amount of CO2
    • Cost-effective and sustainable
    Cons
    • Excludes bottles
    • Difficult to construct

    4. JARDLI Pollen Glass CO2 Diffuser with Bubble Counter

    JARDLI Pollen Glass CO2 Diffuser

    Type Diffuser
    Power Not specified
    Hose tail 4.6 mm
    Product dimensions 4.57 × 2.99 × 1.69 inches

    The JARDLI Pollen Glass CO2 Diffuser is innovative and attractive. The overall glass and delicate design make it visually appealing and easy to blend into a planted aquarium. Not only is it a unique design, but it is also affordable in comparison to other products on the market. Efficient CO2 atomization is made possible through the ceramic membrane to improve the growth and health of aquatic plants. The 0.8-inch diameter is designed for small tanks that are under 20-gallons. This makes it a good option for small, planted tanks, without standing out and ruining the appearance of the

    Pros
    • Visually attractive
    • Designed for small tanks
    • Blends into environment
    Cons
    • Breaks easily
    • Delicate

    5. JARDLI Glass Inline CO2 Atomizer Diffuser

    JARDLI Glass Inline CO2 Atomizer Diffuser System

    Type  Atomizer diffuser
    Power Not specified
    Hose tail 12.16 mm
    Product dimensions 6.6 × 3.35 × 3.15 inches

    This C02 system enhances CO2 dissolution via turbulent mixing which increases the saturation of the CO2 for a balanced planted aquarium ecosystem. The JARDLI Glass Inline Diffuser creates a fine mist of CO2 to increase the absorption of carbon dioxide into the plants. The inline mounting reduces photosynthetic algae growth that can grow on the diffuser disk if it is kept under bright lighting. The inline diffuser has been designed to be installed into the outflow tubing of a canister filter, which can then be mounted below the aquarium or on the outside. This CO2 system fits all types of canister filter tubing.

    Pros
    • Enhances CO2 dissolution
    • Inline mounting reduces algae growth
    • Mist increases absorption
    Cons
    • Must be connected with canister filter tubing

    6. Fibst CO2 Diffuser for Aquarium

    fibst CO2 Diffuser for Aquarium

    Type Diffuser
    Power 7.5PSI air pressure
    Hose tail Not specified
    Product dimensions 13.78 2.76 1.28 inches

    The Fibst CO2 Diffuser can generate completely round bubbles which makes it superior to similar products It is constructed of 304 stainless steel that not only works well as a CO2 diffuser, but also as a simple and elegant design that blends into planted aquariums. This system includes a stainless steel fixture and diffuser and a ceramic sheet. It is important to be made aware that this system requires a 7.5PSI or 0.5 MPa air pressure to generate bubbles effectively. Cleaning is made easy because you remove the sheet for cleaning and not disassemble the entire system.

    Pros
    • Generates round bubbles
    • Affordable
    • Unique design
    Cons
    • Requires a 7.5PSI/0.5 MPa air pressure

    7. Yagote C02 Glass Aquarium Supply Accessories

    Yagote CO2 Glass Aquarium Supply Accessories

    Type CO2 system kit
    Power Not specified
    Hose tail Not specified
    Product dimensions 5.12 × 4.09 × 2.83 inches

    This CO2 diffuser creates a rich amount of valuable CO2 to provide aquarium plants with essential carbon dioxide that the aquarium lacks. It is safe for both plants and other aquatic inhabitants like fish or invertebrates. The glass materials are of high quality which enhances the performance of this system. The ceramic diffuser has atomic pores on the surface which slowly produces fine bubbles that rise slowly to ensure that the carbon dioxide is efficiently diffused in the aquarium.

    The Yagote CO2 Diffuser system is made up of high-quality glass that is difficult to break or damage. The glass reactor is compatible with pressurized tanks over 15-gallons. The design is transparent and appealing and can be hidden behind plants if you do not want a system that is bulky and stands out.

    Pros
    • High-quality glass
    • Difficult to break or chip
    • Transparent and attractive design
    Cons
    • No bubble counter
    • Only suitable for tanks over 15-gallons

    8. MagTool 4L Aquarium CO2 Generator System

    MagTool 4L Aquarium CO2 Generator System

    Type CO2 generator system
    Power 12V DC
    Hose tail 8ft PU Coz proof tubing
    Product dimensions 17.36 × 12.56 × 6.81

    This CO2 system is on the more expensive side when compared to other products on the market, yet it is worth it. This kit includes everything you need to set up a food CO2 system for small aquariums. The needle valve is suitable for 600-800 grams of raw material and the capacity of the system is 4L which makes it long-lasting and durable.

    The bottle is constructed of stainless steel with carbon dioxide grade tubing and includes a plastic funnel and measuring cup. The wall of the bottle meets the safety requirements with a built-in safety valve that will automatically turn off when the pressure exceeds 1137 PSI. It uses DC instead of AC power that runs on a very low voltage and generates minimal heat.

    The design is super quiet and does not hum or vibrate which can disturb the peaceful environment of an aquarium. A downside to this product is that the power required to generate the CO2 gas is not included, and you will need to purchase citric acid and sodium bicarbonate separately. Fortunately, both those products are readily available and cheap, so it should not be an overly discouraging problem if you like the MagTool CO2 system.

    Pros
    • Safe and effective
    • Power saving
    • Generates minimal heat
    Cons
    • Expensive
    • Excludes raw power sources

    Related Read: How To Setup CO2 System For Aquariums: A Complete Guide

    aquarium plant dividerBuyer’s Guide: Selecting The Best Small Aquarium CO2 System

    The most important thing to consider when you are looking for the right CO2 system for your small aquarium is to ensure that the pressurized volume is suited for smaller aquariums. This is because a CO2 system will not function properly if the tank is too small or large. Carbon dioxide can build up rapidly in a small aquarium if the system is not manufactured specifically for that size aquarium. However, many CO2 systems we have mentioned in this article have automatic safety measures in place which allows them to turn off if the pressure exceeds the surrounding area.

    You also want to ensure that the system looks attractive with your aquarium design. Using an unsightly and bulky system can make the tank look unappealing which means you will not enjoy it as much.

    Tips for Buying a CO2 System

    • Ensure that all the items included in the system can meet your needs. If you are new to using CO2 systems in your aquarium, then you probably want to purchase a system that has all the necessary items to get it started.
    • Take the price of the product into consideration. If the product does not come with all the parts to immediately create a good CO2 system, then it will be more expensive to gather the separate products.

    What Kind of Options Are There?

    Size

    There are many different sizes of CO2 systems which can fit into either small aquariums or larger ones. A small tank is typically around 5 to 20 gallons, and different systems can work for specific tank sizes. If it is too big for your aquarium, it can look bulky and not work as effectively as it should. Always check the product dimensions and pressure-volume before you purchase a system for your aquarium.

    small aquarium
    Image Credit: Huy Phan, Unsplash

    Type

    There are many different CO2 systems to choose from. You get atomization emitters, generators, and even DIY kits that allow you to build the system using the purchased materials and using external items like plastic bottles to complete it. Completed setups generally look better in an aquarium, but it comes down to personal preference.

    You might also be interested in: How to Add CO2 to an Aquarium (4 Easy Methods)

    aquarium plant dividerConclusion

    Out of all the products we have reviewed in the CO2 systems category for small tanks, the VIVOSUN Hydroponics CO2 Regulator Emitter System is a good product and makes first place in our recommendations because it is affordable, simple, and does the job right.  The second-best product is the best value choice, the Decadal Aquarium DIY CO2 Generator System Kit because it comes with a variety of materials needed to construct a decent CO2 system that works well for smaller aquariums.

    We hope that this article has helped you find the right CO2 system for your planted aquarium to keep your plants healthy.

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