Colombo CO2 Reactor Set 2.3L

  • Stock: 6 units in stock
  • Model: A5010325
Price: £164.99 £149.999% off
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Skills Required

Better together


This CO2 Reactor Set not only looks super cool but it also functions perfectly and creates pure CO2 from a chemical reaction. After this chemical reaction has taken place in the cylinder the CO2 gas is slowly and constantly released through a pressure regulator. The gas flow can be precisely adjusted with the adjustment knob and integrated bubble counter. The gas flow can be stopped at night with the solenoid which is included with the set and if you connect the solenoid to a domestic timer, you'll have your CO2 coming on and off when your lights are on and off making the gas more economical.

The CO2 Refills are available separately along with the Colombo Drop Checker (recommended) which allows you to monitor your CO2 levels visually.

So it really does tick all the boxes. Looks good, works as expected and fun to make your own CO2 in the comfort of your own home.

So if you are thinking about using pressurised CO2 in your aquarium which will really turbo-boost your plant growth, consider the Colombo CO2 Reactor Kit today. It's a lovely piece of kit, will look stylish in your cabinet and creating your own pure CO2 is both easy and educational.

The bottle is made of stainless steel 314. Supplied with:

  • Bottle holder
  • pressure regulator
  • solenoid valve
  • bubble counter
  • non-return valve
  • outflow
  • accessories and spare parts.

Note: The 2 components to create your carbon dioxide are not included with this set and need to be purchased separately - click here to see them.

You'll also need a euro plug to UK plug adaptor for your solenoid.

This kit stands approx 52cm tall when constructed (in case you wanted to know if it fits in your cabinet).


by Caroline C.
I ordered this for my 240L tank I have newly scaped (My first attempt at scaping). It also has fish and Amano shrimp. I'm using about 3 bubbles a sec. I am very pleased with the product. I wanted a CO2 system that would be easy for a beginner and also one where I didn't have to keep buying disposable canisters. This DIY set up is perfect, the only worry I had was how often I would have to refill it. So far I'm on week 3 and still using the first mix, though I think it will need changing soon as the pressure is now quite low at around 5 (max at start was 20) I have the CO2 start up about 45 mins before my lights turn on and it shuts off about 30 mins before the lights go out. I also purchased the reactor refills at the same time, you get 3 refills in the box and if i get 3 weeks from one set, then the whole box should last me about 9 weeks on my 240L set up. The refills are high quality Sodium Bicarbonate (baking soda) and Citric Acid, they are pre measured and basically, you just

by Ron G.
Very easy to set up. Excellent great value for the money.

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Hi Richard I’ve got the Colombo reactor co2 set and I was wondering if I could fit a co2 bottle full of co2 when I go on holidays because I can be away for a month and my reactor only lasts up to 3 weeks any ideas regards Barry


This isn't poss with the reactor. Probably dangerous too if you tried it.

Hi, I was looking at buying one of these to go replace my JBL kit on a 125l tank but also I'm setting up a 20l tank and I was looking for a co2 kit. Would this be wasted on a 20l tank? i.e. would the contents of the reactor last for months on end or will it slowly dissipate over a period of time? Thanks


Good question - I don't see it being a problem particularly but it is a new piece of kit. The gas is of course trapped in the bottle until released but I don't know for how long. In a 20L tank you need less CO2, but balancing it off against the cost it's still a worthwhile investment for your tank.

Hi, I have a 200 litre tank, roughly how long will the CO2 last, at the moment I have a gas CO2 system and need to know if this would be cheaper in the long run


There's many factors that influence my answer so it's not as straight forward as you would like. Pressurised CO2 from a bottle is more convenient but not necessarily cheaper. It totally depends on your CO2 flow rate, your type of water (hardness) and how much CO2 you want to pump in.

These sets have become popular because you can create your own CO2 easily and they have a much less environmental impact too with no metal to recycle.

If you consider the cost of the refills versus the cost of a gas bottle, I suspect the amount of gas ends up being relatively similar.

Hi, does this have a safety pressure release valve incase the pressure builds up too much, ie, when turned off overnight? Thanks


That's not something to be concerned about as the bottle has been designed to deal with much higher pressures

May I know what the working pressure is of the kit?


Depends on the mix you create and that will change as it depletes 

Hi, I bought the Reactor and have it running well. Am very pleased with it. I have one question though - the bubble counter. The water in it evaporates and I have to refill it every week to be able to see the bubbles clearly. Is this normal? Thanks.


not unusual with bubble counters hence selling bubble counter solution which doesn't evaporate

Hi,can you advise on the dimensions of the reactor when fully assembled? Need to make sure it will fit in my cabinet before purchasing. Thanks

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