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On Orders £30+. Next Day on Orders £80+
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Lifetime Support
With Extended Warranties

Aquarium CO2 Systems

Give Your Aquarium Plants the CO2 They Need to Grow and Flourish

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4.8 / 5

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Providing Excellent Customer Service for 10 Years.

How a CO2 System Will Give You Better Plant Growth in Your Aquarium

If you constantly need to re-stock your aquarium plants because they either die, become overgrown with algae or generally have poor health then you're not alone. It's a problem that every person owning an aquarium has faced at one time or another. But how is it that people are able to create scenes like this...

Aquarium CO2 System shown in a planted tank

...and yet your plants seem to die a few weeks after you planted them? They must be doing something different, right? Correct! Let's look at exactly what they're doing and how you can replicate those results in your own aquarium.

No CO2 = No Photosynthesis = Dead Plants

Diagram of Photosythesis with and without CO2.

"Photosynthesis" - we all learnt about it in school didn't we? No doubt you know this already, but just to refresh, here's a definition of Photosynthesis:

"Photosynthesis is a chemical process through which plants produce glucose and oxygen from carbon dioxide and water, using only light as a source of energy."

Essentially, what this means is without a source of Carbon Dioxide, your aquarium plants can't properly Photosynthesise to produce the sugars they need to survive. Or to put it another way: No CO2 = A Dead Plant.

But how do you give your aquarium plants CO2? Thankfully, it's not as difficult as you might think; just as you use an air pump to pump Oxygen into your aquarium, you can buy Aquarium CO2 Systems to pump Carbon Dioxide into your tank. We'll look into that more further on.

How CO2 Supermarket Can Help You

Since 2010 we have been supplying the world's aquascapers with everything they need to create their own beautiful planted aquarium. For your convenience, we supply pre-bundled CO2 Systems for diffusing CO2 in your aquarium water.

Our Aquarium CO2 Systems Comprise Of

  1. Easy CO2 Adapter (optional)
  2. Gas CO2 Regulator
  3. Bubble Counter
  4. CO2 Diffuser
  5. CO2 Drop Checker
  6. High-grade CO2-resistant tubing
Let's explore the role of each of these parts

Easy CO2 Adapter

Photo of a SodaStream adapter sold in CO2 Systems from CO2 Supermarket. Photo of a SodaStream adapter in use.

One problem you may encounter while operating your CO2 system is actually sourcing the CO2 cylinders needed for your system. Our range of CO2 systems come with an (optional) adapter that enable you to use a range of easily accessible CO2 cylinders as your CO2 source. These include: SodaStream cylinders, Disposable Welding CO2 cylinders, or Paintball CO2 cylinders - simply select which type you'd like.

By using one of these adapters you are assured that a supply of CO2 is always conveniently available from a high street shop. Our CO2 Systems are customisable to enable you to select which adapter you would like to use.

Gas Regulator

Photo of a gas regulator contained in a CO2 System from CO2 Supermarket.

A gas regulator is needed to 'regulate' the high pressure from the CO2 cylinder to a lower, usable pressure for use in the aquarium. Our range of regulators are purpose-built for aquarium use and very safe, easy to install, and use.

The regulators included in our Aquarium CO2 Systems come with an integrated solenoid magnetic valve, which enable use of a timer plug to turn the CO2 off when the lights in your aquarium are switched off and the plants are not Photosynthesising.

Bubble Counter

Photo of a bubble counter attached to a co2 regulator.

A bubble counter is a simple but effective piece of equipment that enables you to monitor the dosing of CO2 into your aquarium. By counting the number of bubbles flowing through the unit, you can adjust the flow controller on the regulator to achieve the 'bubble count' you require.

For example, for a 150L aquarium a bubble rate of 60 bubbles / minute is a good starting point.

The bubble counters that we sell also include an integrated 'check valve' (aka 'one-way valve') that will prevent water from siphoning down the tubing from the aquarium and into your regulator, possibly causing damage.

CO2 Diffuser

Photo of a CO2 diffuser.

Going back to our school days again, in Science lessons we learnt that the rate of a reaction can be increased by increasing the surface area of the reactant, e.g. turning a solid block into a powder. The same principle applies to diffusing the CO2 in your aquarium water; the more surface area the CO2 has in contact with the water, the better the level of diffusion you will achieve. The way to do that is produce very small bubbles of CO2, rather than one large bubble.

The part responsible for this is the 'CO2 Diffuser'. The diffuser emits very small bubbles of CO2. The smaller the bubble, the more surface area, and the better the level of diffusion achieved.

We stock a wide range of diffusers, but the type included in our CO2 systems are known as 'atomizer' diffusers. Atomizer diffusers, as the name suggests, produce incredibly small bubbles of CO2, and therefore achieve very high levels of diffusion.

CO2 Drop Checker

Photo of a CO2 drop checker kit.

A drop checker is deployed within the aquarium and changes colour to reflect the level of CO2 in the aquarium water; yellow indicates too much CO2, blue indicates low CO2 levels, green indicates correct CO2 levels. This eliminates any guesswork as it enables the correct level of CO2 dosing for a specific aquarium. Adjustments can be made using the flow controller on the regulator, and using the bubble counter to monitor the dosing level.

The solution for the drop checker comes pre-mixed, so set-up and installation is done in just a couple of minutes.

CO2-Resistant Tubing

Photo of co2-resistant polyurethane tubing.

To connect your pieces of equipment together you will need to use tubing. It is not recommended to use the same PVC or Silicon tubing used for an air pump because it will react with the CO2 and will eventually crack or become porous, resulting in a leak. Instead we supply high-grade CO2-resistant Polyurethane tubing, which will not react with CO2.

Our Commitment to Customer Service

Over the years we have helped thousands of people successfully install and operate their CO2 system and create the beautiful planted tank they'd always dreamed of. All of our equipment comes with in-depth installation instructions, and we're always on-hand to provide assistance if needed.


Most Popular

Customer Reviews

Average Rating

Individual Reviews

Andy T. Verified Buyer 22nd May 2024
Excellent well made and looks amazing in the tank Excellent well made and looks amazing in the tank 9 Spiral Glass Petal Pollen CO2 Diffuser - For Aquariums up to 180L
Brian B. Verified Buyer 22nd May 2024
Very happy with product (as advertised) and prompt delivery. Thank you. Very happy with product (as advertised) and prompt delivery. Thank you. 4/6mm Clear Polyurethane CO2 Resistant Tubing
Arnold W. Verified Buyer 22nd May 2024
I was (still am) a complete novice when it came to aquariums and certainly co2 systems but it was suprisingly easy to put together and I had it running in no time. I don't really have anything to compare against because this is my first tank and I've used co2 from the start, but my plants dont seem to have any health or growth issues and my carpeting plants are spreading nicely so I can only assume read more... I was (still am) a complete novice when it came to aquariums and certainly co2 systems but it was suprisingly easy to put together and I had it running in no time. I don't really have anything to compare against because this is my first tank and I've used co2 from the start, but my plants dont seem to have any health or growth issues and my carpeting plants are spreading nicely so I can only assume the co2 has worked. Nano Aquarium CO2 System for Planted Tank 20L - 100L
Chris L. Verified Buyer 22nd May 2024
Bought this to replace the crappy JBL one I had before. This is much better and can highly recommend it Bought this to replace the crappy JBL one I had before. This is much better and can highly recommend it CO2 Regulator with Solenoid, Dual Gauges & Adjustable Output Pressure
Don S. Verified Buyer 22nd May 2024
Ive not set it up yet but the service was great and everything received in the system looks very impressive! Ive not set it up yet but the service was great and everything received in the system looks very impressive! Ultimate-Pro Dual Stage CO2 System for Planted Aquarium Tank 20L - 500L+
Daniel K. Verified Buyer 21st May 2024
Smooth transaction, no issues at all, will use again Smooth transaction, no issues at all, will use again Pro Aquarium CO2 System for Planted Tank 20L - 500L+
Steven C. Verified Buyer 19th May 2024
Great product and easy to use. Will save me a fortune on Quooker refills. Well worth the initial outlay. Great product and easy to use. Will save me a fortune on Quooker refills. Well worth the initial outlay. Quooker Cylinder Refilling Adapter
John D. Verified Buyer 17th May 2024
Nice unit and works well. Advisible to fit a check valve below it, otherwise the water will siphon out of it Nice unit and works well. Advisible to fit a check valve below it, otherwise the water will siphon out of it Inline Glass CO2 Bubble Counter
Jamie K. Verified Buyer 17th May 2024
Not used it yet as still getting other bits to start my tank, but no issues with delivery and it all looks good Not used it yet as still getting other bits to start my tank, but no issues with delivery and it all looks good Pro Aquarium CO2 System for Planted Tank 20L - 500L+
Beth W. Verified Buyer 16th May 2024
I can't seem to stop getting aquariums and this is my third kit from CO2 Supermarket and always excellent quality and made to last. I can't seem to stop getting aquariums and this is my third kit from CO2 Supermarket and always excellent quality and made to last. Nano Aquarium CO2 System for Planted Tank 20L - 100L
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