A water filter helps reduce water hardness and filters out substances that can affect the taste and smell of the water. However, it does not completely remove limescale from the water, but typically lowers the water hardness to around 4 to 5 °dH.

Water hardness is measured in degrees of German hardness (°dH). You can easily find the water hardness on your water supplier's website. Simply search for your water supplier's name and find out the water hardness in your area.

There are also various other websites where you can look up water hardness. However, be aware that some of these websites have commercial interests and give the impression that water with a hardness of 6 °dH or higher is already "quite hard." In reality, the quality of German drinking water is excellent. Although it is under pressure due to various developments, it remains among the best in the world. Therefore, in many regions of Germany, using a water filter is not absolutely necessary.

However, water contains far more than just limescale. Substances that affect the taste or smell of the water can also impact the taste of the coffee. If you feel that your tap water has an aftertaste or, for example, smells of chlorine, a water filter can offer significant benefits.

In regions with hard water, generally above 10 °dH, the use of a water filter is recommended. Ultimately, the decision to use a water filter is yours. If you choose not to use a water filter, you should descale your coffee machine regularly.

Remember: A cup of coffee is 98.9% water. Good water quality is therefore crucial – both for the best possible coffee taste and for a long lifespan for your coffee machine.

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