Water hardness in Aalen
12.8 °dH very hard
Tap water in Aalen is very hard: 12.8 °dH (228 mg/L · 13.3 gpg · 22.8 °fH).
Source: Stadtwerke Aalen, Qualität des Aalener Trinkwassers 2023 (Mittelwerte) (2023) · data checked 2026-10-21
Range across supply zones: 205–250 mg/L.
Stadtwerke Aalen publishes mean values for 2023. We computed 227.6 mg/L CaCO₃ from them, within a range of 205.3 to 249.9 mg/L. The figure is a few years old, so check the utility's current report. Heidenheim an der Brenz, 18 km away, is harder at 306.5 mg/L. Expect visible limescale in kettles and showers.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 12.8 °dH |
|---|---|
| Utility | Stadtwerke Aalen GmbH |
How Aalen compares
- Tap water in Aalen is 11 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 352 of 809 in Germany (1 = hardest); 57 % of these cities have softer water.
- In Baden-Württemberg it is number 74 of 146 cities; the regional median is 12.8 °dH.
- Nearest city with clearly softer water: Bopfingen, 19 km away (9.6 °dH).
- Nearest city with clearly harder water: Heidenheim an der Brenz, 18 km away (17.2 °dH).
Ranking of the hardest and softest water in Germany →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Aalen
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 13 °dH |
| AEG / Electrolux | 3 |
| Beko | 4th |
| Hoover | S2 |
| LG | H2 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Aalen water hard or soft?
It is very hard: 228 mg/L as CaCO₃ (13.3 gpg, 12.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Aalen safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
How many grains per gallon is Aalen water?
13.3 gpg, equal to 12.8 °dH, 22.8 °fH or 228 mg/L calcium carbonate.
What dishwasher salt setting should I use in Aalen?
For 228 mg/L (12.8 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Aalen?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Stadtwerke Aalen, Qualität des Aalener Trinkwassers 2023 (Mittelwerte) (2023). Method: computed from supplier's calcium and magnesium. Stadtwerke Aalen, Qualität des Aalener Trinkwassers 2023 (Mittelwerte) · Outdated figure? Tell us