4 Best CO2 Reactors For Your Aquarium

The basics of biology in the natural world is that plant requires carbon dioxide to thrive and be the best and most healthy version of itself possible. On a really basic level, plants, corals and other natural organisms will absorb carbon dioxide in the water, use it to photosynthesis and produce the sugars they need to grow, and then release oxygen as a by-product.

Our Top Pick
Gulfstream Tropical AGU00528

  • Capable of processing between 90 - 250 gallons of water per hour
  • Compact designk
  • Completely diffuses CO2 without producing bubbles

This is the oxygen that other living organisms in your tank, such as fish and snails, will use to survive. It’s a perfect natural balance and an ecosystem that relies on itself to thrive. The same principle applies to trees.

However, unlike the in the actual natural world, CO2 is hard to come across in a fish tank because natural elements aren’t affecting the aquarium and bringing the much-needed CO2 along with it. Your aquarium is a closed off and relatively quarantined environment where it’s hard to get anything from the outside world to enter it.

This is why it’s important to get yourself a device known as a CO2 reactor.

These handy devices naturally add CO2 to your aquarium in a safe and effective way that ensures an optimal oxygen/CO2 balance, helping everything in your tank to live their best life. With this in mind, you’re probably wondering which CO2 reactor is best for you.

Today, we’re going to explore the top four CO2 reactors that are currently available on today’s market, all while detailing everything you need to know about each one so you can pick the one that’s best for you.

Let’s go!

Gulfstream Tropical AGU00528 Ista Max Mix CO2 Reactor for Aquarium (Medium)

Gulfstream Tropical AGU00528 Ista Max Mix CO2 Reactor for Aquarium (Medium)

Starting off our list, we’ve chosen this medium-sized Gulfstream CO2 Reactor that we’re sure you’re going to love. This is a highly rated and highly affordable reactor that’s popular with fish tank owners around the world. Connect this reactor up to a CO2 canister, and away you go!

Thanks to the innovative design of this reactor, you’ll be able to enjoy complete peace of mind since this is a reactor that will diffuse 100% of all your CO2 into the water in an evenly distributed way, all while eliminating CO2 bubbles; a common problem with some reactors.

The installation of this device is very simple since all instructions are included, and there’s no need for any tools or equipment. You’ll also love the fact this design is designed to be as compact as possible, meaning you can set it up practically anywhere in your tank without it getting in the way!

Since this is a medium-sized pump, it’s designed to process between 90-250 gallons of water per hour effectively, meaning it’s suitable for pretty much any small to medium sized tank, which is ideal for most typical fish tank owners!

While this is a more affordable option, and the quality of the parts isn’t as amazing as some of the more premium options, it’s still a device that will last for many years to come, especially when it’s well maintained, and will do everything you need it to when it comes to plugging in it and letting it get on with the job! Perfect!

  • Capable of processing between 90 – 250 gallons of water per hour
  • A compact design so it can be installed anywhere within your tank
  • Completely diffuses CO2 into your aquarium without producing bubbles
  • Simple installation process with no tools required
  • The highly affordable price tag
  • Quality isn’t as solid as other more premium options

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JARDLI Glass Inline CO2 Atomizer Diffuser System for Planted Aquarium Tanks

JARDLI Glass Inline CO2 Atomizer Diffuser System for Planted Aquarium Tanks

If you’re looking for something with a little more quality that’s designed to fit the balance between affordability, functionality, and quality, the Jardli Glass Diffuser is definitely worth your attention. Available in two unique sizes, it’s easy to find a suitable reactor that works for you!

What sets this reactor apart from the rest is the exclusive turbulent mixing system built right into the device. The water comes in one end, has CO2 added to it directly within the device in a clean, even and bubble-free way, before then heading back into your tank. Simple, effective and innovative!

In fact, this reactor adds the CO2 via the fine mist it creates, which is perfect for ensuring there are no little pockets of CO2 trapped in your water.

However, there’s more. You’ll also love the transparent inline design of this device, which not only makes it easy to install and set up anywhere in your tank but is designed to dramatically reduce algae growth which can affect the performance of most reactors.

All in all, this is a super popular inline reactor that gets the job done well, and it’s easy to see how highly rated the device is with customers around the world. The company has recently improved the reactor several times over the last few years, and these are improvements that show; ultimately providing you with a fantastic experience for a good price!

  • Diffuses the CO2 into your tank using a fine mist
  • Comes at an affordable price tag
  • Designed to prevent algae growth on diffuser that can affect performance
  • Has been recently improved to enhance your reactor experience
  • None!

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Tunze USA Diffuser Compact Carbon Dioxide Reactor

Tunze USA Diffuser Compact Carbon Dioxide Reactor

Another simple yet effective inline reactor with diffuser performance properties comes from Tunze; a leading manufacturer of aquarium-based products that are produced at home in the USA. If you’re looking for quality, good old-fashioned manufacturing and design, there may not be any reason to go further than this.

This reactor boasts another handy compact design that’s suitable for pretty much any tank of any size but has a ton of handy features designed to give you the best experience. For example, the design ensures that absolutely no CO2 is wasted during the diffusing process.

This means you won’t have to worry about leakage that could damage your planted fish tank, but you can enjoy a longer lasting CO2 canister without having to go out and buy another one all the time. This is ideal for getting as much bang for your buck as possible!

We also love the fact this comes with a handy magnet holder. This makes installation of the device as simple as placing your reactor anywhere and then sticking into place securely and without the risk of it moving.

Available for a good price and made from sturdy materials, this is one reactor where you really can’t go wrong!

  • Easy installation thanks to the convenient magnet holder
  • Boasts a no-leak design to maximize carbon dioxide output
  • An affordable price tag suitable for all budgets
  • Diffuses carbon dioxide in a bubble-free way
  • Slightly more expensive than typical CO2 reactors

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Sera Flore Active CO2 Reactor 1000 for Large Tanks

Sera Flore Active CO2 Reactor 1000 for Large Tanks

As you can see from these reactors so far, most of them are designed for small to medium-sized tanks, mainly up to the 75-gallon mark, but what if you’re looking for something bigger? What if you have a bigger planted aquarium and you need something with a bit more power? If this relates to you, then this is the reactor for you.

The Sera Flore might come with a premium price tag, but with the level of functionality that won’t be beaten when it comes to any other model. You’ll be able to enjoy top range performance thanks to the built-in motor that’s capable of effectively processing tanks over 160 gallons.

What’s more, you can install this pump to either the inside or the outside of your tank without an issue, and all the installation bits and pieces, including the instructions are included. However, don’t worry; installation won’t take longer than a few minutes, and removing the reactor again to clean it is no hassle whatsoever.

In terms of performance as a reactor, this device is capable of dissolving between 500 and 1,000 bubbles per minute (depending on which version of the model you get), which basically creates a fine mist that evenly distributes the CO2 around your tank.

As you can see, in terms of CO2 reactors, this device is a bit of beast, providing you with an amazing experience that both you and the plant life of your aquarium are going to love. For a long-lasting, high-performance reactor that does everything you’ll need it to, the Sera Flore is a fantastic choice you won’t regret.

  • Capable of effectively processing CO2 into tanks over 160 gallons in capacity
  • All instructions and installation equipment included with your purchase
  • A highly rated model used by tank owners around the world
  • Diffuses between 500 and 1,000 CO2 bubbles per minute
  • None!

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When it comes to getting your aquarium fish tank a CO2 reactor that not only goes above and beyond the call of duty, but also comes at a great price that suits your budget, it’s easy to see there are lots of choices out there for you.
Now all you have to do is pick the one that suits what you’re looking for and then get ready to enjoy your thriving, happy fish tank!