Water hardness in Stupná
0.45 mmol/L soft
Tap water in Stupná is soft: 0.45 mmol/L (45 mg/L · 2.6 gpg · 2.5 °dH).
Source: ČEVAK a.s. (Veolia), Moje obec – kvalita pitné vody (2026) · data checked 2026-10-21
Stupná is supplied by ČEVAK, which reports 45.0 mg/L, so the water is soft. The surrounding Český Krumlov area is largely crystalline bedrock, which is typically low in calcium and magnesium, though the utility does not name the village's source. Scale is minimal, and detergent doses can be kept low.
Czech suppliers report "Vápník a hořčík" in mmol/L; the recommended range is 2–3.5 mmol/L.
Water data
| Total hardness | 0.45 mmol/L |
|---|---|
| Calcium (mg/L) | 7 |
| Magnesium (mg/L) | 6.7 |
| Utility | ČEVAK a.s. |
How Stupná compares
- Tap water in Stupná is 63 % softer than the median of the 1516 cities we track in Czechia (1.2 mmol/L).
- By hardness it ranks 1427 of 1516 in Czechia (1 = hardest); 5 % of these cities have softer water.
- In Jihočeský kraj it is number 479 of 505 cities; the regional median is 1.2 mmol/L.
- Nearest city with clearly softer water: Vrábče, 6 km away (0.33 mmol/L).
- Nearest city with clearly harder water: Lhotka, 3 km away (0.65 mmol/L).
Ranking of the hardest and softest water in Czechia →
What it means at home
- Little or no limescale in kettles, water heaters or washing machines.
- Soap lathers easily; water does not dry skin or hair.
- Dishwasher: salt setting at minimum or off.
- No softener needed; a jug filter only changes taste.
How much salt will you use for softening?
No. Water this soft does not need softening.
Descale a coffee machine or kettle about every 6 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Stupná
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 3 °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 Stupná water hard or soft?
It is soft: 45 mg/L as CaCO₃ (2.6 gpg, 2.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Stupná safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Czech suppliers report "Vápník a hořčík" in mmol/L; the recommended range is 2–3.5 mmol/L.
How many grains per gallon is Stupná water?
2.6 gpg, equal to 2.5 °dH, 4.5 °fH or 45 mg/L calcium carbonate.
What dishwasher salt setting should I use in Stupná?
For 45 mg/L (2.5 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Stupná?
No. With soft water a softener adds nothing.
Source
Source: ČEVAK a.s. (Veolia), Moje obec – kvalita pitné vody (2026). Method: figure published by the water supplier. ČEVAK a.s. (Veolia), Moje obec – kvalita pitné vody · Outdated figure? Tell us