Water hardness in Porto de Mós
64 mg/L moderately hard
Tap water in Porto de Mós is moderately hard: 64 mg/L (3.7 gpg · 3.6 °dH · 6.4 °fH).
Source: Camara Municipal de Porto de Mos - Zona de Abastecimento de Porto de Mos, PCQA 4.º trimestre 2025 (2025-12) · data checked 2026-11-05
The figure comes from the municipal quality report (PCQA) for the Porto de Mós supply zone, fourth quarter 2025: 64 mg/L CaCO₃, moderate. A single quarterly value is a snapshot rather than a guarantee for every street. Scale on kettles and shower screens should be modest.
Portuguese operators report "dureza total" in mg/L CaCO₃ to ERSAR.
Water data
| Total hardness | 64 mg/L |
|---|---|
| Utility | Camara Municipal de Porto de Mos (municipal network, PCQA) |
How Porto de Mós compares
- Tap water in Porto de Mós is 23 % softer than the median of the 77 cities we track in Portugal (83 mg/L).
- By hardness it ranks 50 of 77 in Portugal (1 = hardest); 36 % of these cities have softer water.
- In 09 it is number 6 of 6 cities; the regional median is 92 mg/L.
- Nearest city with clearly harder water: Lagos, 2 km away (95 mg/L).
Ranking of the hardest and softest water in Portugal →
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 Porto de Mós
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 4 °dH |
| AEG / Electrolux | 1 |
| Beko | 1st |
| Hoover | S0 |
| LG | H0 |
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 Porto de Mós water hard or soft?
It is moderately hard: 64 mg/L as CaCO₃ (3.7 gpg, 3.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Porto de Mós safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Portuguese operators report "dureza total" in mg/L CaCO₃ to ERSAR.
How many grains per gallon is Porto de Mós water?
3.7 gpg, equal to 3.6 °dH, 6.4 °fH or 64 mg/L calcium carbonate.
What dishwasher salt setting should I use in Porto de Mós?
For 64 mg/L (3.6 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Porto de Mós?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: Camara Municipal de Porto de Mos - Zona de Abastecimento de Porto de Mos, PCQA 4.º trimestre 2025 (2025-12). Method: figure published by the water supplier. Camara Municipal de Porto de Mos - Zona de Abastecimento de Porto de Mos, PCQA 4.º trimestre 2025 · Outdated figure? Tell us