Water hardness in Mertzig
8.1 °fH moderately hard
Tap water in Mertzig is moderately hard: 8.1 °fH (81 mg/L · 4.7 gpg · 4.6 °dH).
Source: Administration de la gestion de l'eau (AGE), Dureté de l'eau (data.public.lu, CC0) (2022) · data checked 2026-10-20
This figure is over 3 years old; hardness may have changed.
Luxembourg communes report hardness in °fH (and °dH).
Water data
| Total hardness | 8.1 °fH |
|---|---|
| Utility | Commune de Mertzig |
How Mertzig compares
- Tap water in Mertzig is 55 % softer than the median of the 101 cities we track in Luxembourg (18.2 °fH).
- By hardness it ranks 100 of 101 in Luxembourg (1 = hardest); 1 % of these cities have softer water.
- In Diekirch it is number 10 of 10 cities; the regional median is 24.3 °fH.
- Nearest city with clearly harder water: Vichten, 3 km away (25.8 °fH).
Ranking of the hardest and softest water in Luxembourg →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Mertzig
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 5 °dH |
| AEG / Electrolux | 2 |
| Beko | 1st |
| Hoover | S1 |
| LG | H1 |
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 Mertzig water hard or soft?
It is moderately hard: 81 mg/L as CaCO₃ (4.7 gpg, 4.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Mertzig safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Luxembourg communes report hardness in °fH (and °dH).
How many grains per gallon is Mertzig water?
4.7 gpg, equal to 4.6 °dH, 8.1 °fH or 81 mg/L calcium carbonate.
What dishwasher salt setting should I use in Mertzig?
For 81 mg/L (4.6 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Mertzig?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: Administration de la gestion de l'eau (AGE), Dureté de l'eau (data.public.lu, CC0) (2022). Method: figure published by the water supplier. Administration de la gestion de l'eau (AGE), Dureté de l'eau (data.public.lu, CC0) · Outdated figure? Tell us