With hard water (over 14 °dH) yes — it reduces calcification and often improves the taste. With soft water (under 8 °dH) mostly unnecessary. Filters need to be changed every 1–2 months, which causes ongoing costs.

Is a water filter worth it in a fully automatic machine?

With hard water (over 14 °dH) yes — it reduces calcification and often improves the taste. With soft water (under 8 °dH) mostly unnecessary. Filters need to be changed every 1–2 months, which causes ongoing costs.

Why that is

Most fully automatic coffee machines offer the option to insert a water filter directly into the water tank. These filters reduce limescale, chlorine, and sometimes heavy metals in the water. This has two effects: less calcification of the machine and potentially better taste.

Advantages of the integrated filter:

• Less descaling needed. With hard water (over 14 °dH, typical for Berlin, Munich, Cologne), a filter can stretch the descaling interval from 4 weeks to 2–3 months.
• Taste. Chlorine and excess minerals can make the coffee bitter, flat, or chalky. A filter removes these interfering factors.
• Machine protection. Less limescale in the lines means less wear on valves, the pump, and the heating element.

Disadvantages:

• Ongoing costs. Replacement filters cost 5–15 euros each and must be changed every 1–2 months or after 50 liters. Over a year: 30–90 euros.
• False sense of security. Some users think with a filter they never have to descale. That’s not true — the filter reduces limescale but doesn’t remove it completely.
• Water that is too soft. Some filters remove too many minerals. Water that is too soft (under 4 °dH) tastes flat and can attack metal surfaces.

When the filter is worth it:

Water hardness	°dH	Recommendation
Soft	under 8 °dH	Filter mostly unnecessary
Medium	8–14 °dH	Optional, depending on taste
Hard	over 14 °dH	Recommended

Alternative: An external pitcher filter (Brita, BWT) before filling the machine. Cheaper in the long run and more flexible — also works for kettles and other appliances.

In practice at Green Wall Coffee

At Sophienstraße 27, we filter our water centrally through a professional filtration system — Berlin has medium to hard water. For fully automatic machine owners in Berlin, I recommend: either use the built-in filter or a Brita pitcher filter. The difference in taste is clearly noticeable with Berlin water.

Related questions

• Do I need a water filter for my coffee machine?
• What is the ideal water hardness for coffee?
• How often should I descale my fully automatic machine?

Stop by Sophienstraße 27 — Mon–Fri 8am–5pm, Sat 10am–5pm.