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On Orders £30+. Next Day on Orders £80+
Same Day Dispatch
Weekday Orders Placed Before 3pm
Lifetime Support
With Extended Warranties

Aquarium CO2 Systems

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

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Based on 5,496 Customer Reviews.
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

Craig S. Verified Buyer 12th Apr 2024
This is a huge upgrade from the intank diffuser.. I can get a nice mist of super fine bubbles all through the tank. My filter is also recycling the co2 rich water back into the tank This is a huge upgrade from the intank diffuser.. I can get a nice mist of super fine bubbles all through the tank. My filter is also recycling the co2 rich water back into the tank Blizzard Inline Atomizer CO2 Diffuser - for 12/16mm Hose
Edward J. Verified Buyer 11th Apr 2024
Im very pleased with the service and products. Many thanks Im very pleased with the service and products. Many thanks Ultimate-Pro Dual Stage CO2 System for Planted Aquarium Tank 20L - 500L+
Kai L. Verified Buyer 11th Apr 2024
Fast delivery, easy to install and works a treat Fast delivery, easy to install and works a treat Quooker Cylinder Connection Hose (DIN 477 - UK / Europe)
Troy J. Verified Buyer 10th Apr 2024
Very good regulator, seems like excellent quality and super fast delivery too Very good regulator, seems like excellent quality and super fast delivery too CO2 Regulator with Solenoid, Dual Gauges & Adjustable Output Pressure
Colin D. Verified Buyer 10th Apr 2024
Great solenoid. The connector / extension is very useful to connect to my regulator. I also upgraded to the 12v model and I can confirm there's absolutely no noise. Great solenoid. The connector / extension is very useful to connect to my regulator. I also upgraded to the 12v model and I can confirm there's absolutely no noise. CO2 Solenoid Valve for Planted Aquariums
Ronald W. Verified Buyer 10th Apr 2024
Haven't set up my tank yet but seems like good gear. Will write a more in depth review when I've used it. Haven't set up my tank yet but seems like good gear. Will write a more in depth review when I've used it. Pro Aquarium CO2 System for Planted Tank 20L - 500L+
Amanda A. Verified Buyer 8th Apr 2024
Love this regulator, easy to set up and control, built in solenoid which is working great on timer. Love this regulator, easy to set up and control, built in solenoid which is working great on timer. Nano CO2 Regulator with Solenoid Magnetic Valve and Adjustable Output Pressure
Roberto Verified Buyer 8th Apr 2024
this product is truly fantastic, before watering it I had an ADA diffuser with which I delivered 7 bubbles per second to have a concentration of 21 mg/litre, the C02 bubbles were very large and many dispersed upwards, replaced with this fantastic atomizer, everything has changed wonderfully for the better, with only 4 bubbles per second I have the same result of 21 mg/liter of C02 concentration, very read more... this product is truly fantastic, before watering it I had an ADA diffuser with which I delivered 7 bubbles per second to have a concentration of 21 mg/litre, the C02 bubbles were very large and many dispersed upwards, replaced with this fantastic atomizer, everything has changed wonderfully for the better, with only 4 bubbles per second I have the same result of 21 mg/liter of C02 concentration, very small bubbles "a beautiful fog that is distributed in my 225 liters" thanks to the invaluable advice of the team I managed to install everything!! sincere congratulations!! highly recommended UP Inline Atomizer CO2 Diffuser - for 16/22mm Hose
Jonathan C. Verified Buyer 8th Apr 2024
Very speedy delivery, very easy and quick to set up. Would recomend this system and this company. Very speedy delivery, very easy and quick to set up. Would recomend this system and this company. Pro Aquarium CO2 System for Planted Tank 20L - 500L+
Ray J. Verified Buyer 8th Apr 2024
Really good! It's made a huge improvement to my plants. Really good! It's made a huge improvement to my plants. Pro Aquarium CO2 System for Planted Tank 20L - 500L+
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