What is a CO₂ Cylinder?
A CO₂ cylinder (also called a CO₂ canister or gas cylinder) is the pressurised container that stores the carbon dioxide gas used to carbonate your water. When you press the button on your sparkling water maker, CO₂ from the cylinder is injected into the water — creating those satisfying bubbles.
Understanding your CO₂ cylinder is key to getting the most out of your sparkling water maker. Here's everything you need to know.
Types of CO₂ Cylinders
Standard 60L Cylinders
The most common type used with home sparkling water makers. A 60L cylinder contains approximately 400-425g of CO₂ and can make around 60 litres of sparkling water. These are the cylinders that come with most Bubblitz Carbonator Kits.
5kg CO₂ Cylinders
Larger cylinders designed for heavy users, offices, or commercial settings. A 5kg cylinder can produce 600-650 litres of sparkling water — making it far more economical per litre. These require an adapter to connect to standard carbonators.
Food-Grade vs Industrial CO₂: What's the Difference?
This is one of the most important things to understand. Always use food-grade CO₂ for sparkling water.
- Food-grade CO₂ — 99.9% pure, certified safe for human consumption. This is what Bubblitz uses in all our cylinders.
- Industrial CO₂ — May contain impurities and contaminants. Never use this for sparkling water or any food/beverage application.
All Bubblitz CO₂ cylinders contain 100% food-grade, 99.9% pure CO₂. Safe, clean, and certified.
Thread Standards: Why Compatibility Matters
CO₂ cylinders connect to carbonators via a threaded valve. The most common thread standards are:
- W21.8 — The universal standard used by Bubblitz, SodaStream (newer models), Aarke, Drinkmate, and most modern carbonators
- CGA-320 — Used in some older and commercial systems
- TR21-4 — Used by some European models
Bubblitz cylinders use the W21.8 thread, making them compatible with the widest range of carbonators. If you have a different thread, our CO₂ Accessories & Refill Adapters Kit includes adapters for all major standards.
How Long Does a CO₂ Cylinder Last?
This depends on how much you carbonate and how fizzy you like your water:
- Light carbonation (1-2 presses): A 60L cylinder lasts approximately 60 litres
- Heavy carbonation (3-4 presses): Expect around 40-50 litres per cylinder
- 5kg cylinder: 600-650 litres regardless of carbonation level
For a family of 4 drinking 2L of sparkling water per day, a 60L cylinder lasts about 2-3 weeks.
How to Know When Your Cylinder is Empty
Your carbonator will give you less fizz than usual, or you may hear a hissing sound without carbonation. Some models have a pressure indicator. When in doubt, weigh your cylinder — an empty 60L cylinder weighs approximately 800g less than a full one.
How to Refill Your CO₂ Cylinder
Bubblitz offers two convenient refill options:
Option 1: Cylinder Loop Swap Service
Our most popular option. Order a refill online, drop off your empty cylinder, and receive a freshly filled one. No waiting, no fuss. Same-day shipping available.
Option 2: 5kg Cylinder Refill
For heavy users, our 5kg CO₂ Cylinder Refill service offers the best value per litre. Drop off your empty 5kg cylinder and collect a refilled one.
CO₂ Cylinder Safety Tips
- 🔒 Store upright in a cool, dry place away from direct sunlight
- ❌ Never expose to heat above 50°C or open flames
- 🔧 Check connections for leaks before use — a soapy water test works well
- 🚨 Never attempt to refill yourself — always use a professional refill service
- 📅 Check expiry dates — cylinders have a certification date stamped on them
Ready to Stock Up?
Browse our full range of CO₂ cylinders and refills, or grab a Mega Pack bundle that includes everything you need to get started.
Make Water Cool Again. 💧
