How Does a SodaStream Work?

On this page (10 sections)

1. What happens inside a SodaStream?
2. What are the main parts of the system?
3. How does the carbonation button change the fizz?
4. Why does cold water matter?
5. When should you add syrup or flavor drops?
6. What happens when the CO2 cylinder runs low?
7. Which bottles can you use?
8. Does SodaStream make every drink sparkling?
9. What does homemade fizz cost to keep going?
10. How does a SodaStream work, in one sentence?

A SodaStream uses carbon dioxide from a replaceable cylinder to carbonate plain water. Press the carbonation button to choose your fizz level, then add syrup or flavor drops after carbonating.

The basic system has three parts: a CO2 cylinder, a bottle of water, and a machine that controls the gas flow. Bottle connections and button steps depend on the model, so follow its instructions for setup.

What happens inside a SodaStream?

A SodaStream sends pressurized carbon dioxide into water. Some gas dissolves in the water; the rest escapes when you open the bottle, creating the familiar hiss and bubbles.

The CO2 cylinder stores the gas until you press the machine's button. The machine directs gas into the bottle, and the seal lets pressure build while carbonation takes place.

Cold water generally holds carbon dioxide better than warm water. Start with chilled water for a crisp result, while following your machine's fill line and carbonation steps.

A SodaStream doesn't make water or flavor it on its own. It carbonates the water you put into a compatible bottle.

What are the main parts of the system?

The cylinder provides CO2, the bottle holds the water, and the machine controls carbonation. Each part has to fit and be used as its instructions require.

• CO2 cylinder: Holds the gas used for carbonation. Some SodaStream models use a pink Quick Connect cylinder, while other models may use a different connection.
• Carbonating bottle: Holds water as gas enters. Use a bottle made for your machine, and don't fill past its marked line.
• Machine: Holds the bottle and releases CO2 when you press its button. The Terra Value Bundle uses manual operation.
• Flavoring: Syrups and drops go in after carbonation. Adding flavor first can lead to excess foaming.

If you're comparing machines before buying, our guide to SodaStream models explained covers how the model names and features differ. For the basic setup, see how to use a SodaStream.

How does the carbonation button change the fizz?

More button presses send more CO2 into the water, which usually means stronger fizz. Use the sequence your model calls for, and stop at the level you like.

The Terra Value Bundle description says one slow press gives light fizz and a few more build stronger bubbles. Other machines may use a different button sequence or carbonation control, so don't assume every model works the same way.

Start with the minimum recommended carbonation, then add more if your machine allows it. You can adjust the next bottle without using more CO2 than you prefer.

The Terra uses a Quick Connect cylinder and a bottle that snaps into place. Its bundle also includes bubly flavor drops, which are added after the water is carbonated.

Why does cold water matter?

Cold water can hold more dissolved CO2 than warm water, which helps it keep its fizz. Chilling water before carbonation is a simple way to get a livelier drink.

Use plain water that is cold and within the bottle's fill mark. Leave enough room at the top for the machine's carbonation process, as directed in the manual.

Don't put ice in the carbonating bottle unless your machine's instructions allow it. Ice can affect how the bottle sits or how water moves as gas enters.

For more ways to make plain sparkling water at home, see how to make sparkling water at home.

When should you add syrup or flavor drops?

Carbonate plain water first, then add flavor. That order helps reduce foaming and keeps syrup from coating parts intended for water.

After carbonating, pour the water into a glass and stir in syrup or drops. Add a small amount first, taste it, and adjust the next glass to suit you.

The Terra Value Bundle includes bubly flavor drops. SodaStream describes adding Pepsi or Mountain Dew syrups after carbonation; follow your chosen flavor's and machine's instructions.

Don't carbonate juice or syrup unless your machine's instructions say it's allowed. Our guide to putting juice in a SodaStream explains why plain water is the usual starting point.

What happens when the CO2 cylinder runs low?

A low cylinder can produce weaker carbonation or stop making bubbles. Check that the bottle is fitted correctly and that you're following the machine's steps before replacing the cylinder.

Cylinder connections vary. The SodaStream Terra uses a pink Quick Connect cylinder, which clicks into place; other SodaStream models may use a different type.

Match the cylinder to your exact machine before ordering.

The two-cylinder pack is compatible with Terra, ART, Aqua Fizz, E-Terra, E-Duo, Enso, and Gaia models. Each cylinder makes up to 60 liters, though actual output can vary with how much fizz you choose.

When a cylinder runs low, return it through the exchange process or follow the refill instructions for your region. Read how long a SodaStream CO2 cylinder lasts for factors that affect how quickly you go through one.

Which bottles can you use?

Use a bottle that your exact SodaStream model supports. Bottle fit and care instructions differ, so don't rely on capacity or appearance alone.

The SodaStream 1L Slim Bottle twin pack is compatible with SodaStream machines except the Aqua Fizz. Check the compatibility details for your model before buying a spare.

SodaStream describes these bottles as dishwasher safe, but the care instructions say hand wash only. Check the care label that comes with your bottles and follow its guidance.

Don't use a bottle that is cracked, warped, past its stated service life, or not approved for carbonation. A regular water bottle isn't built to hold carbonation pressure.

Does SodaStream make every drink sparkling?

SodaStream carbonates water; you add the flavor afterward. That lets you make plain sparkling water or use a compatible syrup or flavor drop for a different drink.

For plain seltzer, carbonate water and serve it as is. For a flavored drink, add the flavor once the water is in a glass, then stir gently to limit foaming.

A SodaStream is not the same as a machine that carbonates many kinds of liquid. Follow the manual for what can go into the bottle before carbonation.

What does homemade fizz cost to keep going?

The ongoing cost depends on how often you carbonate and how you exchange cylinders. You reuse the machine and bottles, but CO2 cylinders still need to be exchanged or refilled.

Cylinder capacity is an estimate, not a promise that every cylinder will make exactly the same amount. Stronger fizz uses more CO2 per bottle, so it can mean more frequent exchanges.

For a closer look at recurring costs, see SodaStream cost per liter. If you want to compare machine types first, read carbonated water makers: how to choose the right one.

How does a SodaStream work, in one sentence?

A SodaStream uses CO2 pressure to carbonate plain water in a compatible bottle, then you add flavor if you want it. Choose a model and cylinder that fit your needs, and follow the manual for bottle placement, button presses, and cleaning.

Frequently asked questions

How does a SodaStream carbonate water?

A SodaStream releases carbon dioxide from a cylinder into a bottle of water. The gas dissolves in the water under pressure; when you release the pressure by opening the bottle, some gas escapes as bubbles.

The exact button and bottle steps vary by model, so follow that machine's instructions.

Do you put syrup in before or after carbonating?

Add syrup or flavor drops after carbonating plain water. Carbonating flavored liquid can cause it to foam up and spill, and some machines' instructions limit carbonation to water.

Pour the sparkling water into a glass, then add and stir in flavor.

Does a SodaStream need electricity?

Many SodaStream machines use a manual button and a CO2 cylinder, so they don't need an electrical outlet. Electric models are different and need power.

Check your model's instructions before choosing a spot on the counter.

How do I know when a SodaStream CO2 cylinder is empty?

A cylinder is getting low when the machine produces less fizz than usual despite correct bottle placement and button use. Check the cylinder and machine instructions before swapping it.

For model-specific steps, see our guide to changing a SodaStream CO2 cylinder.