Water hardness in Lagos
95 mg/L moderately hard
Tap water in Lagos is moderately hard: 95 mg/L (5.5 gpg · 5.3 °dH · 9.5 °fH).
Source: Águas do Algarve - Edital do 2º Trimestre 2021, Ponto de Entrega de Lagos (2021) · data checked 2026-11-12
This figure is over 3 years old; hardness may have changed.
Portuguese operators report "dureza total" in mg/L CaCO₃ to ERSAR.
Water data
| Total hardness | 95 mg/L |
|---|---|
| Utility | Águas do Algarve S.A. (bulk, Ponto de Entrega de Lagos) |
How Lagos compares
- Tap water in Lagos is 14 % harder than the median of the 77 cities we track in Portugal (83 mg/L).
- By hardness it ranks 27 of 77 in Portugal (1 = hardest); 66 % of these cities have softer water.
- In 09 it is number 2 of 6 cities; the regional median is 92 mg/L.
- Nearest city with clearly softer water: Porto de Mós, 2 km away (64 mg/L).
- Nearest city with clearly harder water: Portimão, 13 km away (120 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 Lagos
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 5 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| 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 Lagos water hard or soft?
It is moderately hard: 95 mg/L as CaCO₃ (5.5 gpg, 5.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Lagos 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 Lagos water?
5.5 gpg, equal to 5.3 °dH, 9.5 °fH or 95 mg/L calcium carbonate.
What dishwasher salt setting should I use in Lagos?
For 95 mg/L (5.3 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Lagos?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: Águas do Algarve - Edital do 2º Trimestre 2021, Ponto de Entrega de Lagos (2021). Method: older figure, source currently unavailable. Águas do Algarve - Edital do 2º Trimestre 2021, Ponto de Entrega de Lagos · Outdated figure? Tell us