Start with hardness.
Use the supplied strip or a suitable water test and enter the result in the machine where a hardness setting exists.
Water changes the taste and the maintenance schedule.
The goal is not mineral-free water. It is water that tastes good, extracts coffee well and does not overwhelm the machine with scale.
Independent general guidance · check the manual for your exact machineMatch the filter to the machine.
Tank filters, filtered jugs and treatment cartridges are not interchangeable. Follow the maker’s compatibility guidance.
A filter delays scale; it does not erase it.
Replace filters on schedule and descale when the machine or manual requires it.
Hardness and alkalinity
Hardness describes minerals that can form scale. Alkalinity affects how water buffers coffee acidity. A single household hardness number is useful but not the whole taste story.
- Use a current local or measured result
- Do not confuse softened water with filtered water
- Re-test after changing treatment
Tank filters
A compatible in-tank cartridge can reduce scale-forming minerals and improve odour, but capacity depends on water and usage.
- Prime the filter exactly as instructed
- Set or reset the replacement reminder
- Never force an incompatible cartridge into the tank
Descaling
Descaling dissolves mineral deposits inside the water path. It is different from removing coffee oils with a cleaning tablet or backflush cycle.
- Use the approved product and dilution
- Complete every rinse stage
- Do not use vinegar unless the manual permits it
Water that should raise a question
Distilled or heavily demineralised water may be unsuitable for taste, sensors or boiler materials. Sodium-softened water may also be a poor fit.
- Read the machine’s water specification
- Avoid guessing from taste alone
- Ask the manufacturer when treatment is unusual
Scale advice is machine-specific
Boiler materials, sensors, heater design and filter systems vary. The manual overrides any general timetable.
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