Brita or BWT: Which water filter is better for coffee?
Both effectively reduce water hardness. BWT additionally enriches the water with magnesium, Brita filters more neutrally. If you want to control your water values precisely, you need a different solution, such as under-sink filters or mineral blends.
Why that is
Brita and BWT are the two dominant table water filter brands in Germany. Both use ion exchange cartridges that remove calcium and magnesium from the water, thus reducing the hardness. For coffee, this is fundamentally positive — less limescale, more aroma, less machine calcification.
Brita (Classic/Maxtra Pro) removes part of the calcium and magnesium via ion exchange. The result is soft, neutral-tasting water. The carbonate hardness decreases, and the pH value shifts slightly towards the acidic side (around 6.5–6.8). Chlorine and taste-impairing substances are removed by activated carbon.
BWT (Magnesium Mineralized Water) goes a step further: the cartridge removes calcium and simultaneously enriches the water with magnesium. The idea behind this: magnesium ions are said to extract coffee aromas particularly well. The pH value is similar to that of Brita.
In practice, the difference between the two filters is subtle for most home users. Both are a significant improvement over unfiltered, hard tap water. Whether you can taste a difference depends on the beans and on how attentively you taste.
Both filters have a limitation: they cannot precisely adjust the water hardness to a target value. The result depends on the input hardness and fluctuates over the lifespan of the cartridge. At the beginning, it filters more strongly, towards the end less so.
If you need precise control, you can turn to alternatives: Under-sink filters deliver more consistent results and are connected directly to the water line. Mineral blends (Third Wave Water) with distilled water allow for an exact brewing water profile, although this takes more effort.
In practice at Green Wall Coffee
For full transparency: at Sophienstraße 27 we treat the water for espresso and filter coffee with a BWT reverse osmosis system. That is not a recommendation for a jug filter, because a café system is something else. Given Berlin's water hardness, either of the two jug filters is better than no filter at all.
Stop by Sophienstraße 27 in Berlin-Lichtenberg — Mon–Fri 8am–5pm, Sat 10am–5pm.
Further reading
In-depth article: How to Make Perfect Espresso · Pour-Over Guide (V60)
Related questions:
- Should I use distilled water for coffee?
- What does Third Wave Water mean?
- Why does my coffee taste different with tap water than in the café?
Also relevant:
- Is a water filter worth it in a fully automatic machine? — Super-Automatic Machines
- Why does oat milk work better in coffee than almond milk? — Milk, Milk Foam & Latte Art
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