Water Hardness Atlas ZIP / postcode

Water hardness in Sihu

161 mg/L hard

Tap water in Sihu is hard: 161 mg/L (9.4 gpg · 9 °dH · 16.1 °fH).

<6060–120120–180>180 mg/L

Source: Taiwan Water Corporation open data (2026) · data checked 2026-10-20

Sihu is reported by Taiwan Water Corporation at 161.0 mg/L CaCO₃ in 2026 (customer tap water). Surface water cannot meet demand on the Choshui alluvial fan, so groundwater is an important source here, which tends to carry more dissolved minerals. At this level scale builds up quickly in kettles, heaters and shower heads, so a softener or scale protection is worth considering.

Taiwan Water Corporation reports total hardness in mg/L CaCO₃; the drinking-water standard is 300 mg/L.

Water data

Total hardness161 mg/L
UtilityTaiwan Water Corporation

How Sihu compares

Ranking of the hardest and softest water in Taiwan →

What it means at home

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 Sihu

BrandSetting for this water
BoschH02
Miele9 °dH
AEG / Electrolux2
Beko3rd
HooverS1
LGH2

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 Sihu water hard or soft?

It is hard: 161 mg/L as CaCO₃ (9.4 gpg, 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 Sihu 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 Sihu water?

9.4 gpg, equal to 9 °dH, 16.1 °fH or 161 mg/L calcium carbonate.

What dishwasher salt setting should I use in Sihu?

For 161 mg/L (9 °dH) check your manufacturer's table: level 4–5.

Do I need a water softener in Sihu?

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 Taiwan Water Corporation open data · Outdated figure?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

Nearby cities

Kouhu169 mg/LShuilin172 mg/LTaixi194 mg/LYuanchang194 mg/LBeigang194 mg/LMailiao160 mg/L
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