Water hardness in Caotun
136 mg/L hard
Tap water in Caotun is hard: 136 mg/L (7.9 gpg · 7.6 °dH · 13.6 °fH).
Source: Taiwan Water Corporation open data (2026) · data checked 2026-10-20
Taiwan Water Corporation's 2026 tap-water data put hardness in Caotun at 136.0 mg/L CaCO₃. Taiwan Water Corporation supplies this district; the raw-water source is not confirmed here. Water this hard leaves heavy limescale on heating elements and taps and shortens the interval between descaling.
Taiwan Water Corporation reports total hardness in mg/L CaCO₃; the drinking-water standard is 300 mg/L.
Water data
| Total hardness | 136 mg/L |
|---|---|
| Utility | Taiwan Water Corporation |
How Caotun compares
- Tap water in Caotun is 8 % harder than the median of the 265 cities we track in Taiwan (126 mg/L).
- By hardness it ranks 123 of 265 in Taiwan (1 = hardest); 54 % of these cities have softer water.
- In Nantou County it is number 9 of 12 cities; the regional median is 160 mg/L.
- Nearest city with clearly softer water: Shetou, 13 km away (100 mg/L).
- Nearest city with clearly harder water: Fenyuan, 7 km away (173 mg/L).
Ranking of the hardest and softest water in Taiwan →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Caotun
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 8 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H2 |
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 Caotun water hard or soft?
It is hard: 136 mg/L as CaCO₃ (7.9 gpg, 7.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Caotun safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Taiwan Water Corporation reports total hardness in mg/L CaCO₃; the drinking-water standard is 300 mg/L.
How many grains per gallon is Caotun water?
7.9 gpg, equal to 7.6 °dH, 13.6 °fH or 136 mg/L calcium carbonate.
What dishwasher salt setting should I use in Caotun?
For 136 mg/L (7.6 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Caotun?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Taiwan Water Corporation open data (2026). Method: figure published by the water supplier. Taiwan Water Corporation open data · Outdated figure? Tell us