Descaler vs cleaning tablets: what’s the difference?

Quick answer: Descaler is an acid that dissolves limescale in the water side of the machine. Cleaning tablets are a detergent that removes coffee oil from the brewing side. They aren’t interchangeable, and most machines need both on different schedules.

Three different cleaning jobs, which machines need which, and why swapping one for the other doesn’t work.

Last updated: September 2026

The three jobs

JobWhat it removesProductHow often
DescalingLimescale in the boiler, thermoblock and pipesLiquid descalerWhen the machine asks; every 1–3 months in hard-water areas
Cleaning (backflush or brew unit)Coffee oil on the group head, shower screen or brew unitCleaning tabletsEvery 200 shots or so on espresso machines; per the programme on bean-to-cups that use them
Milk systemDried milk proteins in the steam wand or carafeMilk cleaner, or a purge and wipeAfter every use (wipe and purge)

Which machines need what

Espresso machines with a portafilter. Every one needs descaling. Machines with a three-way valve, such as the Sage Barista Express, also need backflushing with cleaning tablets — that’s the CLEAN ME cycle. Simpler machines like the Dedica and Stilosa don’t have that valve, so don’t backflush them; just rinse the group head and wipe the shower screen.

Bean-to-cup machines. All need descaling. Some brands run a cleaning programme that uses tablets; De’Longhi’s Magnifica and Dinamica instead have a removable brew group you rinse by hand. Your manual will say which applies.

Pod machines. Descaling only.

Why you can’t swap them

Descaler is designed to dissolve minerals; it does little to coffee oil. Cleaning tablets are designed to lift oil; they don’t dissolve scale. Using the wrong one means the real problem carries on building up.

What to buy

Descaler: use one made for coffee machines.

Cleaning tablets: for espresso machines that backflush, and bean-to-cups whose manual calls for them.

Frequently asked questions

Can I use cleaning tablets to descale?

No. Cleaning tablets remove coffee oil, not limescale. Use a descaler for scale.

Can I backflush a De'Longhi Dedica?

No. The Dedica and Stilosa don’t have a three-way valve, so backflushing with a blind basket doesn’t work and isn’t recommended. Rinse the group head and wipe the shower screen instead.

Is vinegar OK as a descaler?

It’s best avoided. It’s slow, can leave a taste, and can be hard on seals; most manufacturers specify a proper descaler.

Do I need cleaning tablets for a De'Longhi Magnifica?

Generally no. The Magnifica’s brew group is removable and is rinsed by hand weekly. It still needs descaling when the light comes on.

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