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With Extended Warranties

Aquarium CO2 Systems

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

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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.

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 Aquarium CO2 Systems to pump Carbon Dioxide into your tank. 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 CO2 Systems 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 Aquarium CO2 Systems 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 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 ensuring 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 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

Customer Reviews

Average Rating

Individual Reviews

William P. Verified Buyer 19th Nov 2018
I am so impressed with CO2 supermarket - not just because of the products but for their knowledge of what parts are needed for unusual situations, their responsiveness and their willingness to go over and above with their customer service. I can’t rate them highly enough. Thank you!!! I am so impressed with CO2 supermarket - not just because of the products but for their knowledge of what parts are needed for unusual situations, their responsiveness and their willingness to go over and above with their customer service. I can’t rate them highly enough. Thank you!!! CO2 Cylinder Refilling Adapter
Steven G. Verified Buyer 16th Nov 2018
Yeah, does what it says on the tin. Yeah, does what it says on the tin. Regulator CO2 Bubble Counter With in-built Check Valve
Adrian T. Verified Buyer 14th Nov 2018
A very good product, problem is the connection to the master cylinder thread. Depending on the bottle thread, the adapter is not always in the same position when tightened. A very good product, problem is the connection to the master cylinder thread. Depending on the bottle thread, the adapter is not always in the same position when tightened. SodaStream Cylinder Refilling Adapter
Javier S. Verified Buyer 12th Nov 2018
Incredibly fine bubbles. You have to wait 5-10 minutes for it to work as in the beginning because of whatever reason very big bubbles appear. But after that 10 mins the bubbles are so fine you can't imagine. For the purists that want to see crystal clear water 100% of the time I'd recommend a reactor, as the bazooka will produce a mist that will be seen until 10-15 minutes after the solenoid goes off read more... Incredibly fine bubbles. You have to wait 5-10 minutes for it to work as in the beginning because of whatever reason very big bubbles appear. But after that 10 mins the bubbles are so fine you can't imagine. For the purists that want to see crystal clear water 100% of the time I'd recommend a reactor, as the bazooka will produce a mist that will be seen until 10-15 minutes after the solenoid goes off (or whatever) but for those who already have a polen glass and are thinking on an inline or a bazooka this is definitely the way to go. I couldn't be more satisfied. Bazooka Atomizer CO2 Diffuser - 70mm for Aquariums up to 300L
Steven . Verified Buyer 9th Nov 2018
This is my first co2 system and as such I was a bit apprehensive about the whole thing from setting it up to the wellbeing of the fish. Before purchase I e-mailed co2 supermarket for advice on what system would best suit my needs, I received a prompt reply with advice and recommendation I took the plunge and ordered the system which arrived the next day. When you receive your order conformation e-mail read more... This is my first co2 system and as such I was a bit apprehensive about the whole thing from setting it up to the wellbeing of the fish. Before purchase I e-mailed co2 supermarket for advice on what system would best suit my needs, I received a prompt reply with advice and recommendation I took the plunge and ordered the system which arrived the next day. When you receive your order conformation e-mail it contains links on how to set up the system, I watched these videos a few times and followed them to the letter which lead to a problem free set up. The system as been running with no problems whatsoever, and I can already see the benefit in plant growth and vigour. The fish behaviour never altered or changed. So everything is going great. The only regret I have is I never purchased the system earlier. Im using sodastream co2, and bubble count of 1 bubble per second. Plugged into a timer switch for the system to turn on two hours before lights on and turn off one hour before lights out. Pro Aquarium CO2 System with Adjustable Pressure for Planted Tank 20L - 500L+
Rob V. Verified Buyer 7th Nov 2018
good quality and gives nice bubbles. good quality and gives nice bubbles. Regulator CO2 Bubble Counter With in-built Check Valve
Silvana D. Verified Buyer 7th Nov 2018
Good product and excellent customer service, answering all my questions large and small. I had a problem with with mine after a few uses, it was exchanged with no quibbles and very quickly. I would definitely recommend Good product and excellent customer service, answering all my questions large and small. I had a problem with with mine after a few uses, it was exchanged with no quibbles and very quickly. I would definitely recommend SodaStream Cylinder Refilling Adapter
Franck P. Verified Buyer 6th Nov 2018
sodastream adapter received in 4 days to France, fast delivery, adaptation to the easy sodastream bottle. CO2 diffusion is perfect, thank you sodastream adapter received in 4 days to France, fast delivery, adaptation to the easy sodastream bottle. CO2 diffusion is perfect, thank you Advanced Adapter for SodaStream Cylinders
Simon B. Verified Buyer 5th Nov 2018
Did just what I wanted. Good price and very prompt service. Did just what I wanted. Good price and very prompt service. SodaStream Adapter Seal / Washer (2 pack)
Derek C. Verified Buyer 31st Oct 2018
Just got it up and running this week and everything was straight forward to set up. Took a few days to get the drop checker to change from blue to green but got there eventually. The bubble counter is a little erratic so adjust it carefully. I got the 60mm Bazooka atomizer diffuser and it really is fine, I can see the fine bubbles swirling around the aquarium. As I said it's still early days but so read more... Just got it up and running this week and everything was straight forward to set up. Took a few days to get the drop checker to change from blue to green but got there eventually. The bubble counter is a little erratic so adjust it carefully. I got the 60mm Bazooka atomizer diffuser and it really is fine, I can see the fine bubbles swirling around the aquarium. As I said it's still early days but so far everything is ok. Advanced Aquarium CO2 System for Planted Tank 80L - 500L
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