CO₂ Cartridges vs Carbon Filters: What's Actually in Your Tap

If you own a sparkling water tap, two consumables keep it running: a CO₂ cartridge and a carbon filter. They're often confused. They do completely different jobs.

The carbon filter

• Job: remove chlorine, sediment and organic taste compounds from incoming mains water.
• How long it lasts: ~6 months or ~2,000 litres, whichever comes first.
• Symptom of a dead filter: chlorine taste returns, water pressure drops.

The CO₂ cartridge

• Job: carbonate the water at the point of dispense.
• How long it lasts: ~60 litres of sparkling water per 425g cartridge (varies by carbonation level).
• Symptom of an empty cartridge: sparkling function delivers still water, or fizz noticeably weaker.

Subscribing beats forgetting

Both items have a predictable replacement rhythm. A household of four averages one CO₂ cartridge per month and one filter every six. That's why we offer subscription refills — the boxes arrive before you notice you're low, and you save 10% versus one-off orders.

Cartridges are 100% recyclable (aluminium body, steel valve). We include a prepaid return label with every subscription order.