Gero Onsen (Soto Pump Station)
Analysis UnverifiedGero Onsen counts among Japan's three famous springs, and legend holds that when its waters once vanished, a white heron alighted on the Masuda riverbank to reveal a new gush. The Gero Onsen Soto pump station source draws on several centrally managed wells and sends them on to inns throughout the hot-spring town. Its pH 8.9 alkaline water glides softly over the skin and lingers as a light, refreshed feeling, soothing travelers who stroll the hot-spring town and seek gentle rest.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
Mild antibacterial action keeps the skin clean. Trace transdermal absorption supports tooth and bone health.
A trace component with gentle antibacterial and anti-inflammatory action.
- Alkaline (pH)pH 8.9
- Feel
- Feels slippery and silky on the skin.
- Said to
- Said to remove old skin cells and excess sebum.
- Note
- Skin can dry out afterwards—moisturize after bathing.
- Metasilicic acid57.3 mg/kg
- Feel
- Your skin may feel smoother.
- Said to
- 50 mg/kg or more is said to mark a “skin-beautifying spring”; it is also used in skincare.
- Note
- The “skin-beautifying” label is a common rule of thumb, not a legal standard.
- Source temperature56.2℃
- Feel
- The source is 42°C or hotter; the bath may be on the hot side.
- Said to
- Heat is said to boost circulation and warm the body.
- Note
- Older people and those with high blood pressure or heart conditions should avoid baths of 42°C or more. Keep soaks short.
Effects are general descriptions based on the Ministry of the Environment’s indications by spring type, not a guarantee.
Scores are calculated from mineral analysis data based on the Mineral Spring Analysis Guidelines (Ministry of Environment, Japan). They are unrelated to facility atmosphere or service quality.
▸Note
The temperature, pH and component values shown here are based on the hot spring analysis (source). Actual values in the bath may differ depending on heating, dilution, recycling and filtration. Please check current usage status at the facility.
With a smooth pH 8.9 alkaline touch, go light on soap and let the water glide over the skin. As a mild simple spring, it suits an unhurried 10 to 15 minute soak at a moderate temperature.
With a pH of 8.9 and 57.3 mg/kg of metasilicic acid, this water is traditionally associated with silky skin, gently softening the outer layer. As a mild simple spring, it may also support deep relaxation on days when work or travel fatigue needs to be eased.
Avoid bathing during acute illness or with serious heart or lung conditions. The source reaches 56.2°C, so check the bath temperature before entering.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Gero Onsen (Soto Pump Station)
- Spring type
- Alkaline Simple Hot Spring
- Source temperature
- 56.2℃
- pH
- 8.9
Analysis Document
- Analysis date
- 2013-11-25
- Analyst organization
- 一般財団法人 岐阜県公衆衛生検査センター
- Registration No.
- 岐阜県第二号
Cations
- Sodium ion Na⁺
- 118 mg/kg
- Potassium ion K⁺
- 2.2 mg/kg
- Magnesium ion Mg²⁺
- < 0.1 mg/kg
- Calcium ion Ca²⁺
- 4.4 mg/kg
- Aluminum ion Al³⁺
- 0.06 mg/kg
- Manganese ion Mn²⁺
- < 0.001 mg/kg
- Iron(II) ion Fe²⁺
- < 0.02 mg/kg
- Total cations
- 125 mg/kg
Anions
- Fluoride ion F⁻
- 10.3 mg/kg
- Chloride ion Cl⁻
- 113 mg/kg
- Hydrogen sulfide ion HS⁻
- < 0.1 mg/kg
- Sulfate ion SO₄²⁻
- 12.4 mg/kg
- Bicarbonate ion HCO₃⁻
- 37.5 mg/kg
- Carbonate ion CO₃²⁻
- 24.1 mg/kg
- Nitrate ion NO₃⁻
- 0.40 mg/kg
- Total anions
- 198 mg/kg
Undissociated Components
- Arsenious acid HAsO₂
- 0.10 mg/kg
- Metasilicic acid H₂SiO₃
- 57.3 mg/kg
- Metaboric acid HBO₂
- 7.0 mg/kg
- Total undissociated
- 64.4 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- < 4 mg/kg
- Free hydrogen sulfide H₂S
- < 0.1 mg/kg
Totals
- Total dissolved substances
- 387 mg/kg
- Component total
- 387 mg/kg
Usage
- Heating
- No
- Dilution
- No
- Recycle / Filter
- No
- Additives
- No
- Disinfection
- Yes
Indications & Contraindications
- Bathing indications
- Autonomic instability, Insomnia, Depression
- General indications
- High blood pressure (mild), Rheumatoid arthritis, Chronic pain or stiffness in muscles and joints, Muscle stiffness due to motor paralysis, Gastrointestinal dysfunction
- Contraindications
- Acute illness (especially with fever), Active tuberculosis, Malignant tumors, Severe heart disease, Respiratory failure, Renal failure, Bleeding disorders, Severe anemia, Any actively progressing illness, Pregnancy (especially early and late stages)
Drinking
- Drinkability
- Not drinkable
