Carbon dioxide is one of the most useful gases we supply – and one of the most confusing to buy. The same gas pours a perfect pint, keeps a planted aquarium thriving, carbonates sparkling water, chills frozen drinks and fills confetti cannons. So when someone searches for a “CO₂ cylinder”, the honest first question is: what are you using it for?
This guide clears it up. We will explain what a CO₂ cylinder actually is, walk through the bottle sizes Adams Gas supplies, match the common uses to the right size, and show you how to get a refill delivered locally or collected from a stockist near you – all on a rent-free basis.
What is a CO₂ cylinder?
A CO₂ cylinder is a steel bottle holding carbon dioxide under pressure, where most of the contents sit as a liquid with gas above it. As you draw gas off, more liquid evaporates to replace it – which is why a CO₂ bottle keeps delivering at a steady pressure until it is nearly empty.
The CO₂ itself is graded for its job. The cylinders most people need are food grade (the E290 designation), meaning the gas is pure enough to come into contact with food and drink – for draught beer, sparkling water, frozen-drinks machines and similar uses. The same food-grade CO₂ is also ideal for hydroponics and planted aquariums, where purity matters for healthy growth.
CO₂ cylinder sizes
Adams Gas supplies CO₂ in a wide range of sizes, from disposable canisters up to large refillable trade cylinders. Here is how the everyday options compare:
| Cylinder | Type | Best suited to | Notes |
|---|---|---|---|
| 580g / 1,100g disposable | Single-use, food grade | SodaStream-style filling, small hydroponics & aquarium setups, hobby use | Lightweight, no rental – see the disposable food-grade range |
| 1.5kg | Refillable, food grade | Home bars, small sparkling-water and aquarium setups | The most popular entry size for the home |
| 3.15kg | Refillable, food grade | Busy home bars, frozen-drinks machines, larger aquariums | A common SodaStream-cylinder refill size |
| 6.35kg | Refillable, food grade | Home and light trade draught, paintball, special effects | Available with a dip/siphon tube where liquid CO₂ is needed |
| 15kg | Refillable, food grade | Pubs, bars and venues with steady demand | A long-running trade workhorse |
| 34kg | Refillable, food grade | High-volume hospitality and industrial use | Longest run time between changes |
The smaller disposable canisters suit anyone who wants CO₂ on tap without committing to a larger bottle – ideal for refilling a SodaStream-style cylinder, dosing a planted aquarium or running a compact home setup. The refillable 1.5kg to 6.35kg sizes are the sweet spot for home bars and hobbyists, while the 15kg and 34kg cylinders are built for pubs, bars and trade users who get through gas quickly.
Not sure how much you have left? Our guide on how to tell if your cylinder is almost empty explains a simple way to check before you run dry mid-service.
What can you use a CO₂ cylinder for?
Carbon dioxide is genuinely one of the most versatile gases we stock. Common uses include:
- Draught beer & cider at home – CO₂ pushes beer from keg to tap and keeps it carbonated. Pair it with our home bar gas range.
- Sparkling water – food-grade CO₂ refills SodaStream-style and compatible cylinders. See SodaStream & small cylinder filling.
- Hydroponics & indoor growing – enriching the air with CO₂ supports faster, healthier plant growth. Browse CO₂ for hydroponics & plant growth.
- Planted aquariums – a controlled CO₂ supply helps aquatic plants thrive. We supply dedicated aquarium CO₂ in small, easy-to-manage sizes.
- Frozen-drinks machines, special effects, paintball and more – the same food-grade CO₂ runs slush machines, stage effects and confetti cannons.
For pubs, bars and event venues, CO₂ is part of a wider dispense setup that often uses mixed beer & cellar gas too. If that is you, our beer & cellar gas supply guide explains the CO₂, nitrogen and mixed-gas options in detail.
Rent-free CO₂: why it matters
Here is where Adams Gas stands apart from the big industrial suppliers: our CO₂ cylinders are rent-free. With many traditional suppliers you pay an ongoing cylinder rental or standing charge whether or not you use the gas – costs that quietly add up year after year.
With Adams Gas you pay for the gas and the cylinder, not for the privilege of keeping it in the corner. For a busy pub that is a meaningful saving; for a home brewer or aquarium hobbyist it removes the barrier of a rental contract entirely. We explain the full picture in our rent-free cylinders guide.
Where to buy and refill CO₂ near you
When your cylinder runs low you have two simple routes:
- Exchange – swap an empty bottle for a full one.
- Refill – top up a refillable cylinder.
Adams Gas makes both easy. You can order CO₂ for local delivery – see our gas bottle delivery service – or collect from one of the independent retailers in our nationwide stockist network. Browse the full CO₂ bottles range to find the size that fits your setup.
A quick safety note: CO₂ should always be stored upright in a ventilated space and handled with care. Our short guide on handling and storing CO₂ safely covers the essentials.
The right cylinder, no rental, supplied locally
A CO₂ cylinder is simple once you start from the use, not the label: pick disposable or 1.5–3.15kg for home bars, sparkling water and aquariums, 6.35kg for heavier home or light-trade use, and 15kg or 34kg for busy hospitality. Choose food grade for anything touching food, drink or living plants, and enjoy it all rent-free.
If you run a pub, bar or growing business and want a dependable CO₂ supply – or you would like to stock Adams Gas products yourself – become a stockist or browse the CO₂ range to get started.
