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 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
Berlin has medium to hard water. For fully automatic machine owners in Berlin, I recommend: either use the built-in filter or a pitcher filter. The difference in taste is clearly noticeable with Berlin water.
You'll find us at Sophienstraße 27 in Berlin-Lichtenberg, Monday to Friday 8am–5pm and Saturday 10am–5pm.
Further reading
In-depth article: Drip Coffee Machine Guide
Related questions:
- How to clean my fully automatic coffee machine properly?
- How often should I descale my fully automatic machine?
- Which descaling agent is the right one?
Also relevant:
- Do I need a water filter for my coffee machine? — Water & Water Quality
- Is an expensive coffee grinder really worth it? — Grinding & Grind Size
All questions in this topic: Super-Automatic Machines