Descaling agent

A mild acid (citric, lactic, or sulfamic) used to dissolve calcium carbonate buildup inside an espresso machine boiler. Sold as powder, tablets, or liquid.

Why it matters — Descaling restores flow and heating efficiency in a scaled-up machine. But descaling is harsh — aggressive acids damage seals, copper components, and aluminium parts. Use only when necessary, and follow manufacturer instructions.

Good to know

• If you have good water filtration, you should rarely if ever need to descale. Filtration is the long-term answer; descaling is the emergency one.
• Avoid pure citric acid solutions — they can corrode brass and aluminium. Use manufacturer-approved descaling agents that include corrosion inhibitors.

Related: Descaling