The Best CO2 Reactors for Aquarium for 2023

One of the things that you need to ensure when maintaining a fish tank is keeping carbon dioxide and oxygen balanced inside the tank. To do this, you need to get an efficient CO2 reactor that is specifically designed to aid in adding an adequate amount of carbon dioxide immediately and without any difficulty.

The reason why it is essential and practical to purchase the top-tier CO2 reactor is that these devices serve a very vital role in naturally adding carbon dioxide into the fish tank. For a fact, it has been proven that it can work wonders in providing risk-free and efficient means of ensuring carbon dioxide and oxygen balance.

As you might already know, when O2 and CO2 are balanced, it could help your aquarium pets thrive and enjoy their dwelling place. Considering this, you might be contemplating what carbon dioxide reactors will work most suitable for your needs and style.

Continue reading the rest of this article and explore more on the different carbon dioxide reactors reviewed below. In so doing, you can reduce the stress and time wondering what type of CO2 reactor would top-rated solve your concerns.

Selecting the best CO2 reactor is much more than buying fancy-looking products. It requires understanding several vital aspects to ensure you choose a suitable option. So before we look at the reviews, here's a quick overview of some:

  • Budget: CO2 reactors aren't the cheapest product or a bargain-buy device. So you'll need to set aside quite some money unless you're buying products from Chinese manufacturers, such as Yidao. In this case, the price may even be lower than $20, but it can be hard to get hold of them.
  • Ease of Installation: Never purchase a CO2 reactor with pump or without a pump that doesn't offer an easy installation process. It also should come with all the required equipment and instructions for a DIY job.
  • Durability: CO2 reactors aren't always built to last a long time. So it's vital to do extensive research into each model's design materials. If you do, separating the durable ones from the lemons will be much easier.

With the following product reviews below, you can learn more about the features and functions that you need to ponder to get what's suitable for you.

Best Overall


Sera CO2 Reactor

✔ Sturdy acrylic materials
✔ Easy to assemble & clean
✔ Noiseless and leak-free operation


Premium Choice


WuyouChy CO2 Reactor Kit

✔ Durable overall construction
✔ Consistent and dependable performance
✔ Assembling is not a laborious task to manage


Editor’s Choice

Gulfstream Tropical AGU00529 Ista Max Mix Co2 Reactor

Gulfstream Tropical AGU00529

✔ Very affordable and light in weight
✔ Does not need any tools for assembly
✔ Resistant to any form of impact and acidity


List of Top-Rated CO2 Reactor Reviews 2023

1. Sera Flore Active CO2 Reactor


Are you exhausted searching for the most appropriate CO2 reactor for a planted aquarium? It is true that shopping for one may be tricky. Luckily, Sera Flore Active CO2 Reactor can satisfy your requirements in keeping your fish and plants healthily thriving inside the fish tank.

This device is made of durable acrylic materials. There is no need to worry about installing it since setting it up and disassembling it is painless. You can instantly mount it internally or externally. As compared with other models, this operates without generating any irking noise and it can guarantee a leak-free operation.

Once purchased, it already includes hose connections that come with fasteners and suction cups. This does an excellent job of mixing carbon dioxide into the water with the aid of a return line from an exterior canister filter. What is more, it is capable of breaking the bubbles up quite well.

In essence, this unit won't let you down if you are aiming for superior performance when it comes to totally dissolving carbon dioxide into the water.

However, you need to be aware of this device's downsides that, including the useless hose union nuts. Maybe consider utilizing hose clamps instead. And, when using it, be sure to use a strong filter.

  • Can guarantee top-range performance specifically in comprehensively dissolving carbon dioxide
  • Easy to assemble, clean and maintain
  • Built with sturdy acrylic materials
  • Ensures noiseless and leak-free operation
  • Can be mounted internally or externally
  • May require a strong filter
  • Useless hose union nuts

Over and above, this carbon dioxide reactor appears to be a more dependable and efficient device to consider as compared to investing in a ceramic diffuser. It does a superb job at dissolving nearly all the carbon dioxide in the water. It is easy to install and does not require tedious and time-consuming cleaning and maintenance processes. It is durable and it is not a hassle to mount internally or externally.

Meanwhile, you need to take note of its few drawbacks such as its worthless hose union units and the need to utilize a strong filter when operating it.

2. WuyouChy CO2 Reactor Kit


If you are eyeing to purchase a professional CO2 diffuser, then this device is worth a try. It is made of a stainless steel bottle that is sturdy and dependable enough to use. This is regarded as a very cost-effective product to invest in mainly because all the necessary accessories to set it up are included in the package once bought.

What set it apart from other available units available on the market these days are its very solid stainless steel construction and a safety valve that opens in an automatic mode when it exceeds the safe pressure. As you can see, this makes it risk-free to utilize even for beginners who are not that insightful in doing the job.

This CO2 reactor is user-friendly. That said, you don't need to be a pro in keeping a fish tank to operate it. It is easy to use and its simple design is actually what makes it preferable to other long-time fish tank keepers. If you hope to keep the carbon dioxide fairly balanced inside the aquarium, then this unit can help you execute that.

Not the less, this isn't strong enough to handle fish tanks that are larger. In other words, its capacity might only be limited to servicing smaller tanks. Furthermore, the actual assembly process isn't that intricate and can be figured out on your own. In truth, what makes it complicated are the poorly written instructions.

  • Known for being efficient, sturdy, consistent and dependable performance
  • Already includes the required accessories once purchased
  • Designed with safety valve that automatically opens when it exceeds the safe pressure
  • Assembling is not a laborious task to manage
  • Durable overall construction that could last for years
  • Only highly recommended for smaller tanks
  • Comes with complex assembly instructions

In summary, you won't waste a cent investing in this carbon dioxide reactor. Its solid overall construction makes it effective, reliable, steady and durable to utilize. It is safe to operate in that it is equipped with an automatic safety valve that opens on its own when it goes beyond the safe pressure. There is no need to purchase various accessories separately because all of these are already included in the package.

This is practical too especially to anyone who is not that acquainted with such a device- it means that you don't need to look for all the accessories that you will need to operate the unit. Be that as it may, this device will only work quite well for smaller tanks and may only provide limited performance for larger tanks. And, its assembly instructions are useless too.

3. Gulfstream Tropical AGU00529 Co2 Reactor

Gulfstream Tropical AGU00529 Ista Max Mix Co2 Reactor

If you opt for a CO2 reactor aquarium that is compact, efficient and lightweight, then this is the right match for you! Indeed, you can get this item at a pocket-friendly price tag and it can be instantly sealed if you prefer.

This device comes with a patented impeller design that makes it quite adept at reducing carbon dioxide bubbles. In the same way, its Max Mix Reactor has the capacity to dissolve carbon dioxide in the water exhaustively.

This is user-friendly too. So, even if you are a beginner in this hobby, it is a piece of cake to set up and use. You won't even need to prepare some tools to install it. All you need to ensure is that you follow the assembly procedures accordingly.

Unlike other models out there, this device won't give you a hard time when cleaning and maintaining it.

On the other hand, this CO2 reactor comes with a removable bottom but this makes it a little leaky, and to solve this problem, you may consider permanently sealing it using epoxy or silicone. Also, this product appears frail especially at the hose connections.

  • Very affordable and light in weight
  • No sweat to fit precisely where you require it
  • Does not need any tools for assembly
  • Comes with a feature that's resistant to any form of impact and acidity
  • Max Mix Reactor is capable of completely dissolving carbon dioxide into the water
  • Comes with removable bottom but it's slightly leaky
  • Seems fragile at the hose connections

Overall, this device's efficiency, compactness, lightweight and ease of use features are what make it a very good deal to consider. You can fit it precisely where you prefer or require it to be, either inside or outside. And, it can resist any form of impact and acidity- this only proves to say that it is constructed with sturdy materials.

But, it's helpful to note a couple of its weak points such as its removable bottom that is slightly leaky so you need to seal it with epoxy or silicone and it could be frail at the hose connections too.

4. ISTA Turbo CO2 Reactor Diffuser


Are you having difficulty deciding and mulling over the CO2 reactor vs. diffuser? Then, you can end your agony with ISTA Turbo CO2 Reactor Diffuser. This device will surely meet your requirements and satisfy your expectations if you seriously wish to provide your fish tank inhabitants with an adequate amount of carbon dioxide for them to thrive and enjoy their stay inside the aquarium.

To boot, this unit is not very much like other brands that only give you headaches with various leak issues. Likewise, it is easy to put together and immediately fasten it into the canister filtering system. Priced with a slightly costly selling price, this is still worth considering given its avant-garde features that you can't find in other units.

Nonetheless, this device must be stringently handled with extra caution. It seems to be brittle, so it could be damaged quite easily if not given proper care. The hose barbs appear to be short in length, which is contrary to what was advertised. Anyway, if these defects aren't a big deal to you, then this is a good buy for you to try!

  • Designed with compact size and assembly is a no-brainer
  • Can guarantee exceptional carbon dioxide dissolution into the water
  • Does not call for an excessive flow rate to operate properly
  • Capable of helping plants healthily survive fish tank life
  • No sweat to fasten into the canister filtering system
  • Slightly brittle so it requires handling with extra care
  • Hose barbs seem to be short in terms of length

To conclude, this carbon dioxide reactor diffuser product is a nice investment that you won't be upset about. Even though it is slightly pricey, you can't find anything disappointing when it comes to its sterling performance, ease and convenience of use. It is not a pain in the neck to assemble and you'll like its compact size.

Unlike other units, this doesn't necessitate an extensive flow rate for it to function accordingly. You can even instantly hook it into the canister filtering system in a few minutes. This is one great solution for you to consider if you want your aquatic plants to obtain sufficient amounts of CO2 to survive fish tank life.

Still, if you do not prefer short-length hose barbs and if you think you're not the careful type of user, then maybe this won't be the perfect option for you to invest in. This device is fragile and needs to be used or operated with much caution.

5. Gulfstream Tropical AGU00528 Co2 Reactor


This CO2 reactor complements the fish tank setup quite well. Furthermore, you can finish the assembly process in minutes and there is no need to prepare any tools to install it. To ensure the precise position of the device, see to it to carefully follow the instructions located on the side of the box. Whether you prefer to mount it internally or externally, this can be easily done as it can fit accurately where you most need it.

You'll love this CO2 reactor's durability. As a matter of fact, this is smooth sailing to clean and maintain and it even has the capability to resist any form of impact and acidity. This is highly recommended for small to medium-sized tanks. And, it does not matter whether you are still a newbie or already a pro in the field of aquarium hobby. This unit is certified user-friendly.

Aside from these, it does not come with a costly price tag. Considering its extraordinary features, it is surprising to get this at a pocket-friendly price. This device's innovative design allows fish tank owners to be worry-free as it can efficiently diffuse nearly all the carbon dioxide into the water in a fairly distributed manner.

Nevertheless, two of the weak spots that you need to pay attention to regarding this unit are it’s susceptible to leakage problems and some audible noise to be expected when you start injecting the carbon dioxide.

  • Can totally alleviate carbon dioxide bubbles, made possible by its patented impeller design
  • No tools needed when installing it
  • Comes with a compact design that can be easily mounted internally or externally
  • Capable of resisting any impact and acidity
  • Can guarantee infallible and efficient performance
  • Produces noticeable noise when injecting carbon dioxide
  • Prone to leakage problems

To sum things up, this device is the perfect choice for anyone who would like to invest in a compact, efficient, durable and easy-to-set up carbon dioxide reactor. This is well-known for its capability to disperse carbon dioxide excellently. Built with a patented impeller design, this enables the unit to get rid of carbon dioxide bubbles comprehensively.

Anyhow, a few of the negative sides of this unit include some leakage problems and the fact that it has the potential to generate some noise, particularly when you begin to inject CO2. Amidst these defects, this is still a nice CO2 reactor that's worth spending in.

6. JARDLI Glass Inline CO2 Diffuser 


This JARDLI model comes with very durable and well-built glass that makes it stunning, comes with an expensive look and can provide a satisfying performance. Apart from this, the inline mounting alleviates the amount of algae accumulation inside the aquarium and tubing that, eventually resulting in a clean and low-maintenance fish tank. Since the glass is solid, it is less likely to get damaged easily. This carbon dioxide reactor can disperse CO2 quite efficiently and it is fascinating to see micro bubbles coming out pleasantly.

It is worth noting that what makes this truly a good item to splurge in is that as compared to other models that require to be sealed with silicone or epoxy to stop leaking issues, this device won't give you the stress of dealing with leak concerns because it does not leak at all. You'll like its simple yet solid design and construction.

For all that, this device is designed with a fairly short connecting tube that commonly calls for zip ties or other types of connectors to consolidate it together. And, it is normal for it to generate an audible sound when in use.

  • Inline mounting minimizes photosynthetic algae buildup on the diffuser disc
  • Capable of forming sheer mist of carbon dioxide to improve plant growth as well as absorption better
  • Specifically built to be set up inline in the canister filter's outflow tubing
  • Designed with solid and well-constructed glass
  • Requires low maintenance and easy cleaning procedure
  • Comes with fairly short tube connectors
  • A little noisy while operating

In general, this device is a surefire purchase. It does a great job of making it a lot easier for fish tank owners to move the hood that shelters their lights and covers the fish tank. And, since it is not positioned beneath the fish tank lights, it is less likely to get filled with algae. And, it works outstandingly in forming several small bubbles that dissolve more exceptionally in the water flow returning from the canister filtering system. Superb performance, durability and ease of assembly, low maintenance and top-rated performance are what constitute this device.

However, just like other units, this device also comes with a few imperfections that you need to know. Its tube connectors are slightly short, so you will need to consider using zip ties and other forms of connectors to put them together. Also, this CO2 reactor cannot promise a silent operation whenever you use it.

Outdated Products

ISTA 80076 Co2 External Reactor (Outdated)


This model is deemed one of the top-notch aquarium CO2 reactors available these days. In order to enable it to operate silently and smoothly, it calls for a lower flow rate. This is known for having the capability to provide superior overall performance even though it may produce the audible sound at first.

In addition, once the reactor is full right after tuning up the filter, the audible sound luckily goes away. This operates quite well and you will be surprised to see a fascinating carbon dioxide level in the tank without those soda-like bubbles. You can get this at a very affordable price tag which makes it even more of a great deal to try since it can provide many years of service.

Still and all, please be guided that when you operate this carbon dioxide reactor, there is a possibility for it to generate some noise. Although the sound is not too annoying, it is loud enough to be heard. Aside from this, it may considerably lessen the flow rate of the canister. These are just a few of the flaws that you need to check out about this model.

  • Highly recognized for its long lifespan
  • Most preferred for its ease and convenience of use
  • Can operate smoothly and ensure superb overall performance
  • Sold at a decent price tag
  • Comes with simple design and is well-sealed
  • May generate some noise
  • Has the tendency to reduce the canister's flow rate significantly

In a nutshell, you won't regret getting this carbon dioxide reactor for your fish tank. With its durability, it is preferred by many wise consumers because it can provide reliable service for many years. It is easy to set up and very convenient to utilize. It could guarantee outstanding overall performance, provided you strictly adhere to the assembly and usage procedures. For the money, this is a great catch. You'll love its simple design and it comes well-sealed too.

Anyway, a couple of the imperfections that you need to watch out for regarding this model are its tendency to produce some audible noise whenever you start to operate it. But, this actually lasts only for a few minutes. And, you also need to consider its potentiality to minimize the flow rate of the canister seriously.

Awesome Aquatics Inline CO2 Diffuser Reactor (Outdated)


This device is a must-have. It comes with top-drawer features that you could ever ask for in a carbon dioxide reactor unit. If you're going to inspect its overall construction, you'll see that it is made of premium quality materials and lasts for many years of usage. You can immediately mount it internally or externally since it is designed with a wall mount bracket.

More than that, this CO2 inline reactor is also good at immensely reducing the likelihood of algae accumulation inside the fish tank. As you know, this would be of great help in keeping your aquarium pets safe, happy and healthy. With its exceptionally upgraded availability and absorption of CO2, it could efficiently guarantee successful plant growth.

Whether you plan to use it in your existing system or for your newly-bought system, this can be easily utilized. In line with this, it is uncomplicated to assemble, and best of all, cleaning and maintenance no longer need to be an exhausting and time-consuming task for you to deal with.

Regardless, this carbon dioxide inline reactor always necessitates the use of clamps on any hose connections. And, just like other available models out there, a slight noise is to be expected when you start to operate this device.

  • Enables improved absorption and availability of carbon dioxide to ensure maximum plant growth
  • Proudly made of heavy-duty overall construction
  • Designed with a wall mount bracket
  • Significantly aids inhibit algae buildup in the fish tank
  • No trouble to set up on already existing or newly-purchased systems
  • Always requires the use of clamps on any hose connections
  • Slight noise may be expected when operating

All in all, this device is a wise investment that is worth trying. It does not only supply a sufficient amount of carbon dioxide inside the tank, but it also does wonders in warding off the possibility of algae growth in the aquarium. It is a breeze to set up and you won't even need to consume more time cleaning and maintaining it. You can mount it anywhere you prefer. It isn't that expensive at all, so you have nothing to lose but more to gain in the long run.

Meanwhile, take in mind that some audible noises are possible to be heard as you begin operating this unit. And, it always requires the use of clamps on any hose connections for it to guarantee out-of-the-ordinary overall performance.

What To Look For When Buying An Aquarium CO2 Reactor


When it comes to buying a suitable carbon dioxide reactor for you, aside from thinking through the price tag of the device, it also matters to opt for the one that can provide you with the possible top-tier performance.

In detail, here are the valuable factors or features that you need to look through before you invest in a CO2 reactor:

Budget. Needless to say, the carbon dioxide reactor model that you choose will highly rely on the amount of money you are willing to spend on the device. There are cheaper brands that come with stunning features and there are expensive models that can provide extraordinary performance.

No matter your preference, the only thing that matters the most, in the end, is the quality of the device you decide to buy. Thus, do not only settle on affordability, also inspect if the quality is not compromised.

Compact design. This could make the device a lot easier to set up in the tank anywhere you prefer.

Capable of exhaustively dispersing carbon dioxide into the fish tank in a bubble-free approach.

Easy installation process. Luckily, many models these days are no sweat to set up and they do not even require other tools to put them together.

Algae growth blockage. The CO2 reactor must also be capable of inhibiting the proliferation of algae inside the aquarium. This is one efficient way of keeping your fish tank pets healthy and safe.

No leakage issues. The device should be designed to help maximize CO2 output. See to it that it is not prone to leaking.

All installation equipment as well as assembly instructions must be included in the package once purchased. At times, you can also get products that also include the required accessories necessary to operate the unit.

Taking into account all the factors aforementioned prior to the final buying decision will surely help you choose the one that does not only suit your budget but could also satisfy your needs and style. Hence, keep all these reminders in mind when getting yours.

Other Important Factors to Consider


What is a CO2 reactor for aquarium? How does it work?

Carbon dioxide is difficult to change in an aquarium precisely because natural components are not affecting the fish tank and it makes it impossible to bring the necessary carbon dioxide along with it. As you know, a fish tank is comparably a confined environment where it is quite complex to obtain anything from the outside world to access it. That said, it is no wonder why getting a carbon dioxide reactor for you is a must to consider if you're keeping an aquarium.

A CO2 reactor is a practicable device that is particularly built to add carbon dioxide to the fish tank in a natural mode. This unit serves a vital role in that it can efficiently and safely guarantee O2 and CO2 balance inside the tank. It especially aids everything inside the aquarium to live a safer, healthier and happier life. This is why it is specifically important to get the best co2 reactor to help you achieve this.

The good news is that different CO2 reactor models nowadays come with innovative designs. Therefore, as a fish tank owner, you can finally be at peace knowing that the device could exceptionally disperse all your carbon dioxide into the water and this could be done in a uniformly distributed approach. At the same time, this is executed in a bubble-free mode.

What are the different types of aquarium CO2 reactors?

Fundamentally, the carbon dioxide reactor is deemed as the most costly diffuser that is capable of supplying the greatest output of carbon dioxide; however, this definitely comes at a decent price and it is primarily utilized for large-sized fish tanks.

The top-quality types of CO2 reactors are those that create bubble-free performance, do not come with leakage issues and can evenly distribute the carbon dioxide into the water. Other types ensure a secure and safe performance, and most importantly, these are capable of warding off serious algae growth inside the tank.

Take note that different types of reactors are made in various materials such as solid glass, stainless steel, high-quality plastic and the like.

Why do you need a CO2 reactor? (Benefits)

The primary objective of a CO2 reactor is to enable carbon dioxide contact time with the water. This device performs excellently by adding nothing more within the tank.

The use of a carbon dioxide reactor is inevitable in that this device is quite more efficient than diffusers or atomizers and this is especially practical for anyone who cannot stand carbon dioxide mist inside the aquarium.

Without any doubt, the device's dissolution and efficiency rate highly banks on the design of the specific CO2 reactor as well as the rate of flow of the pump or canister filtering system that operates it. It is possible to fasten the unit to the filter outputs; however, it slightly lessens the flow.

Bear in mind that reactors can only manage a specific maximum injection rate for their size or design. Evidently, this only proves to say that it is definitely critical to pick the appropriate size for your tank.

Using a top-quality and reliable carbon dioxide reactor can ensure the following perks:

  1. Such a device could help impede the immense buildup of algae inside the fish tank. Obviously, this is one way of keeping the aquarium free of any harmful bacteria that may endanger the lives of your fish tank occupants.
  2. This does a great job of helping aquarium keepers ensure a balanced amount of oxygen and carbon dioxide inside the tank. For people who prefer bubble-free mode, this is the most suitable option to consider.
  3. It is not difficult to set up, use and operate. This unit is actually user-friendly, so newbies in aquarium hobby won't have a hard time using it even if it is their first time to run it in the tank.
  4. Various brands or models are generally sold at affordable price tags. They aren't difficult to find and there are plenty of sizes, designs and styles that you could freely select from for your fish tank.
  5. The use of this device helps aquatic plants to happily and healthily survive dwelling in a confined environment like an aquarium. And, this is made possible by a CO2 reactor that aids in supplying the right amount of carbon dioxide for them to flourish.

Frequently Asked Questions


Is a CO2 reactor better than a diffuser?

There are several areas where a high-quality CO2 reactor is better than a CO2 aquarium diffuser. For instance, reactors are much more durable with less extensive maintenance requirements.

Another area where CO2 reactors are better is their efficiency. These devices use less gas than a typical diffuser when doing their job. As a result, aquarium owners won't have to fill up their CO2 as often with a reactor.

Furthermore, CO2 reactors function at much lower pressures than a traditional or inline CO2 diffuser. So it doesn't put high pressure on connections within your aquarium. It's just another aspect that makes our lives easier.

However, diffusers also provide benefits that reactors don't offer—these devices are less expensive and don't produce as much noise. So it's easy to see how an aquarium enthusiast may choose diffusers over a reactor.

But if you're looking for quality, a top-tier CO2 reactor like Sera Flore Active CO2 Reactor is better than any available diffuser.

Can too much CO2 hurt fish?

An abundance of CO2 can hurt your tank's fish. In fact, if the CO2 reaches toxic levels (over 30 PPM), it could become fatal for your fish. They’ll end up suffocating from their inability to get oxygen.

It's why buying a high-quality CO2 reactor like ISTA 80076 Co2 External Reactor is vital. These devices will help maintain ideal CO2 levels. As a result, your fish will only benefit from the CO2 presence rather than suffer from it.

Where should you place your CO2 reactor?

Most experts suggest placing CO2 reactors wherever a tank's maximum current is located. This placement provides the top-rated environment to let the reactor do its job effectively. It's certainly done wonders in my planted tank.

After all, this placement allows the current to move around the bubbles effectively. It'll do the same thing for the CO2 dissolution in your tank's water. So please, set up your new CO2 reactor at this location and marvel at the results.

What are the most trusted CO2 reactor brands?

As discussed previously, there are a number of carbon dioxide reactor models that come in various features and functionality. All of them also come in different price ranges that aiding in making the selection process a less challenging task to deal with. There are top-rated brands that you can freely choose from and the most notable ones include the following:

  • Sera Flore Active CO2 Reactor
  • Gulfstream Tropical AGU00528 Ista Max Mix Co2 Reactor
  • Awesome Aquatics Inline CO2 Atomizer Bubble Diffuser Reactor
  • JARDLI Glass Inline CO2 Atomizer Diffuser System
  • ISTA 80076 Co2 External Reactor

How to add CO2 to aquarium?

There are various methods to supply the CO2 in your fish tank. In general, this falls into 2 categories: liquid or gas injection. These techniques are broadly available from nearly all online fish tank specialists on the web.

Take into consideration that the formula will greatly rely on the size of your fish tank. Moreover, carbon dioxide is not dispersed in the fish tank by means of a diffuser, but this is done directly into the water; the reason for this is the inadequacy of pressure.

Hence, it is critical for you to install the system on your own. See to it that the system should be replaced once every few weeks.

When adding CO2 into the water, connect the reactor to the external filter. When the carbon dioxide bubbles already reach the internal section of the reactor, these will be consistently broken down till they are totally dissolved into the water.

A friendly reminder: Please refer to the recommended amount of carbon dioxide to be added to your fish tank. This is usually indicated in the product you buy, or if not, it won't hurt if you conduct research about it. Consider the size of your tank and the type of aquarium pets you are presently keeping. As you know, an excessive amount of carbon dioxide could also cause danger to your fish tank inhabitants.

How to install?

  • Buy a carbon dioxide generator kit. This kit commonly includes the plastic tubing that attaches two caps and also comes with a valve and a pressure gauge. At times, the tubing will be attached by a piece of solid plastic.
    Meanwhile, the valve and the pressure gauge are especially designed to enable users to keep track of and control the amount of carbon dioxide that goes into the aquarium.
  • Tighten the pressure gauge cap to the above portion of the citric acid bottle. Afterward, embed the tubing that comes out of the cap into the bottle indicated as B. You may start turning the cap in a clockwise mode till it becomes really tight.
  • Then, it is time to tighten the cap that comes with the valve connected to the bottle of baking soda. After that, carefully turn the valve in a clockwise pattern to close it tightly prior to fastening the bottles. Put the tube that comes out the cap with the valve fastened to the above portion of the bottle of baking soda. Lastly, turn the cap again in a clockwise mode to screw it.
  • Fasten the end of the tubing to a bubble counter. This is the tiny plastic piece that the carbon dioxide disperses through prior to directly going into the tank. Make sure to supply the bubble counter with water. After that, seize the plastic tubing coming from the valve and embed the end into your bubble counter.
  • Attach the bubble counter to the extra tubing. Take the longer tubing for it to reach the tank's bottom part easily. Get the tubing and link it to the output valve found on the bubble counter's bottom part.
  • Fasten the diffuser to the end section of the tubing. Then, you're done installing your carbon dioxide system setup.

How to use?

Different carbon dioxide reactor models come in slightly different methods of how to use them. By happy chance, the usage instructions and assembly procedure are printed and can be found inside the package once you buy the item.

The step-by-step process on how to set up the device properly is detailed in the manual. See to it that to follow the directions by heart to avoid various problems like leakage and other malfunction-related issues brought about by the improper installation of the device. Always refer to the product's manual when assembling it. Also, you may refer to the installation technique or procedure discussed in this article.

How to care & store?

Carbon dioxide reactors are actually a piece of cake to utilize, operate, clean and maintain. On the other hand, it is highly advised to take extra caution when using those made with fragile materials like glass-made versions.

While many of these products are made of superior quality glass materials, it cannot be denied that no matter how solid the glass is, this is still and will always be prone to getting easily damaged. As a result, without extra caution, you end up breaking them.

When it comes to cleaning CO2 reactors, one effective means to remove the dirt accumulated on the device is using chlorine bleach or water solution. Be sure to deeply soak the device in water solution or chlorine bleach for a few hours. Then, wash and rinse the device until it becomes completely free from the cleaning solution.

If you decide to keep the device, it matters to store it in a place away from children and somewhere where it won't be accidentally damaged. If your device is glass-made, make sure to cover it with bubble wrap or anything that could provide more protection so to keep it from being cracked or broken. This is also to shield you and your loved ones from injuries. Make it a habit to clean the device before you store it.

Where to buy?

Fortunately, carbon dioxide reactors are not quite difficult to find. In point of fact, these devices generally come in distinct designs, sizes, shapes, features and price ranges. You can begin shopping by checking out nearby pet or fish stores in your area.

Alternatively, suppose you prefer to shop online. In that case, you may visit eBay, Walmart, PetSmart, Amazon, PetCo and plenty of other legit and credible online shopping sites that you can come across on the web. Be sure to use the right keywords when typing your search so they can narrow down your choices and make it a lot easier for you to decide which one most suits your needs and preferences.

Additional Information

If your aquarium is suffering from vegetation or foliage issues, then one way to solve this problem is by injecting the water with carbon dioxide. This will do a wonderful job of enhancing the safety and health of your aquatic plants. However, if you do not prefer buying your CO2 reactor, then you can consider doing it yourself.

To create your own carbon dioxide reactor system, you will need a bottle (preferably 2 liters in size), fish tank equipment and tubing. Instructions on DIY CO2 reactors are available on YouTube. You can check out the one you like best. These guides are easy to follow even for beginners.

Undoubtedly, this is a very cost-effective alternative to buying costly carbon dioxide systems from local fish or pet stores and even on the web.

But, the DIY process may be tedious and time-consuming as compared to buying it on the market. Whatever you prefer, you can decide for yourself. What matters most is having a reliable and efficient CO2 reactor that can help supply the necessary amount of carbon dioxide into the tank water.


The living creatures dwelling inside your fish tank especially require a balanced amount of oxygen and carbon dioxide for them to thrive in a confined environment. And, for you to auspiciously, safely and efficiently add the necessary carbon dioxide into the water, it is crucial to invest in the best CO2 reactor.

Not to mention, by simply utilizing the most outstanding one for your fish tank, your aquarium pets will have everything they require for them to live healthily and happily inside the tank. Through the detailed product reviews above, you can certainly pick out the brand that you think will best match your current requirements and style.

It is worth mentioning that an affordable price tag that is appropriate for all budgets is not the only vital purchasing factor for you to contemplate on. You also need to pay attention to the product's features and functions as these two will mostly matter in the long run.

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