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Free Global Shipping
On Orders £20+. Next Day UK Orders £80+
Same Day Dispatch
Weekday Orders Placed Before 3pm
10 Year Warranty
With Lifetime Help & Support

Aquarium CO2 Systems The Easy Way

The Aquarium CO2 Specialists who give you Free Global Shipping*, Free Returns & Free Expert Advice

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How to Get 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...

Photo of a planted aquarium

...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.

Your Aquarium is a Closed Ecosystem

The most important aspect you need to consider is that you are creating an artificial world for your plants and fish, encased within glass or plastic. What that means is the nutrients and elements that your plants need don't occur as they do in the wild, and just as you feed your fish to satisfy their needs, your plants also need to have their needs satisfied too.

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 kits to pump Carbon Dioxide into your aquarium. We'll look into that more further on.

Nutrients & Elements

Any plant, whether aquatic or terrestrial, needs a variety of nutrients to grow and maintain a good state of health. In the wild these nutrients are provided by natural means but because an aquarium is a closed ecosystem those nutrients must be supplemented to maintain strong growth and good health. If those nutrients aren't supplemented the plant will eventually die, or certainly have a lacklustre appearance.

Plants require nutrients at different rates and volume, some are required at higher volumes, such as Potassium (K), Phosphorus (P), and Nitrogen (N) - these are known as 'Macronutrients'. Other nutrients are also required, but at lower amounts or concentrations. These are know as 'Micronutrients' and include elements such as Boron (B), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mo) and Zinc (Zn).

But how do you go about sourcing those nutrients and elements? They sound more like things you'd find in a Science laboratory rather than a pet store. Well, just as with the CO2 aspect, we can help with this too.

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 kits for diffusing CO2 in your aquarium water, and also complete aquarium fertiliser mixes that contain all of the required nutrients and elements to sustain vigorous plant growth in your aquarium.

Our Kits Comprise Of

  1. Easy CO2 Adapter (optional)
  2. Gas 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 kits 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 ensuring that a supply of CO2 is always conveniently available from a high street shop. Our kits are customisable to enable you to select which adapter you would like to use.

If you know you can source a supply of CO2 cylinders and an adapter won't be needed, then you can choose from our 'Kits without Adapters' range.

Gas Regulator

Photo of a gas regulator contained in kits 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 kits 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 without problem. All of our equipment comes with in-depth installation instructions, and we're always on-hand to provide assistance if needed.


Most Popular

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Individual Reviews

Ian J. Verified Buyer 10th Dec 2016

Does the job well. Soleniod quiet. Just be sure t...

Does the job well. Soleniod quiet. Just be sure to use spanners to ensure tight fit. Does the job well. Soleniod quiet. Just be sure to use spanners to ensure tight fit. CO2 Regulator with Solenoid & Dual Gauges for Vertical Cylinder Valves
Igor V. Verified Buyer 9th Dec 2016

very good control of flow. I like this product

very good control of flow. I like this product very good control of flow. I like this product Inline CO2 Needle Valve for Planted Aquarium Systems
Yaron Verified Buyer 9th Dec 2016

Excellent product and good service delivery was ve...

Excellent product and good service delivery was very fast Excellent product and good service delivery was very fast CO2 Regulator with Solenoid & Dual Gauges for Vertical Cylinder Valves
Thomas H. Verified Buyer 9th Dec 2016

This complete set was ordered one year ago, and ha...

This complete set was ordered one year ago, and has worked very well all the time. I was impressed with the service from CO2 Supermarket at that time also. This complete set was ordered one year ago, and has worked very well all the time. I was impressed with the service from CO2 Supermarket at that time also. Complete Aquarium CO2 System with SodaStream Adapter for Planted Tank 80L - 500L
Valentín C. Verified Buyer 8th Dec 2016

Very satisfied with the service, all right

Very satisfied with the service, all right Very satisfied with the service, all right Essential Fertiliser & Minerals Mix - 250g
Keith S. Verified Buyer 6th Dec 2016

Cannot comment as purchased for christmas present ...

Cannot comment as purchased for christmas present but sure it will work. QUICK DELIVERY THANKS Cannot comment as purchased for christmas present but sure it will work. QUICK DELIVERY THANKS Complete Aquarium CO2 System with SodaStream Adapter for Planted Tank 80L - 500L
John E. Verified Buyer 5th Dec 2016

Good buy. I recommend this seller

Good buy. I recommend this seller Good buy. I recommend this seller Reactor CO2 Diffuser - Medium for Aquariums up to 200L
Jenny F. Verified Buyer 4th Dec 2016

The bubble counter, press out the water until ther...

The bubble counter, press out the water until there is nothing left after a few weeks. Oderwise perfect The bubble counter, press out the water until there is nothing left after a few weeks. Oderwise perfect Precision Inline CO2 Bubble Counter with Check Valve


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Reply from CO2 Supermarket
This is normal, water evaporates. Use baby oil instead, which won't evaporate.

Alessandro G. Verified Buyer 3rd Dec 2016

Diffusore di co2 eccellente micronizza in maniera ...

Diffusore di co2 eccellente micronizza in maniera ecezzionale per quanto riguarda la spedizione nulla da dire visto la distanza arrivato integro e nei tempi previsti. Diffusore di co2 eccellente micronizza in maniera ecezzionale per quanto riguarda la spedizione nulla da dire visto la distanza arrivato integro e nei tempi previsti. Bazooka Atomizer CO2 Diffuser - 60mm for Aquariums up to 120L
António F. Verified Buyer 1st Dec 2016

I was very impressed by the speed of shipping my o...

I was very impressed by the speed of shipping my order. So I think I'll buy things back on your site I'm grateful. Best Regards A Ferreira I was very impressed by the speed of shipping my order. So I think I'll buy things back on your site I'm grateful. Best Regards A Ferreira CO2 Regulator with Solenoid & Dual Gauges for Horizontal Cylinder Valves
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