Water hardness in Cantù
32 °fH very hard
Tap water in Cantù is very hard: 32 °fH (320 mg/L · 18.7 gpg · 17.9 °dH).
Source: Como Acqua - Dati qualità dell acqua (aggiornati al 31 agosto 2026) (2026) · data checked 2026-10-29
Como Acqua's data, updated to 31 August 2026, record a measured hardness of 320 mg/L CaCO₃ (32 °f) for Cantù. The water is very hard. A descaler on the kettle or a softener on the mains is the usual practical response, though the source does not describe the supply.
Italian utilities report °f (French degrees); D.Lgs. 31/2001 recommends 15–50 °f.
Water data
| Total hardness | 32 °fH |
|---|---|
| ca_mg_l | 106 |
| mg_mg_l | 14 |
| Utility | Como Acqua Srl |
How Cantù compares
- Tap water in Cantù is 51 % harder than the median of the 629 cities we track in Italy (21.2 °fH).
- By hardness it ranks 71 of 629 in Italy (1 = hardest); 88 % of these cities have softer water.
- In Lombardia it is number 11 of 142 cities; the regional median is 24.9 °fH.
- Nearest city with clearly softer water: Mariano Comense, 6 km away (17 °fH).
- Nearest city with clearly harder water: Locate di Triulzi, 43 km away (40.3 °fH).
Ranking of the hardest and softest water in Italy →
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 Cantù
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 18 °dH |
| AEG / Electrolux | 4 |
| Beko | 5th |
| Hoover | S3 |
| LG | H3 |
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 Cantù water hard or soft?
It is very hard: 320 mg/L as CaCO₃ (18.7 gpg, 17.9 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Cantù safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Italian utilities report °f (French degrees); D.Lgs. 31/2001 recommends 15–50 °f.
How many grains per gallon is Cantù water?
18.7 gpg, equal to 17.9 °dH, 32 °fH or 320 mg/L calcium carbonate.
What dishwasher salt setting should I use in Cantù?
For 320 mg/L (17.9 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Cantù?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Como Acqua - Dati qualità dell acqua (aggiornati al 31 agosto 2026) (2026). Method: own measurement. Como Acqua - Dati qualità dell acqua (aggiornati al 31 agosto 2026) · Outdated figure? Tell us