Bubbles 101: Our carbonating cylinders are the heart of your Sparkling Water Maker. It perfectly fits your Sparkling Water Maker and contains colorless, odorless, incombustible gas, used to help create the bubbles.
With a gas exchange, you return any empty SodaStream cylinder and just pay the price of the gas for a new cylinder. You can easily exchange your carbonating cylinder at a store near you.
A spare cylinder is there so you never run out of gas. You pay for the cylinder and the gas, and there's no need to return an empty cylinder. SodaStream recommends having at least 3 cylinders on hand, so you’ll always have bubbles and so you can exchange 2 at a time.