# SCA Coffee Water Calculator
Calculate custom mineral recipes for specialty coffee according to SCA guidelines for TDS, hardness, alkalinity, and pH.What is the SCA water standard?
What is the SCA water standard?: The Specialty Coffee Association defines target ranges for hardness, alkalinity, pH, and sodium to support balanced extraction and protect equipment.
Why should I not use tap water directly?: Tap water changes by city and season. Chlorine, scale, or unbalanced minerals can mute specialty coffee and damage boilers. Mineralising distilled water gives repeatable results.
Where can I get the mineral salts?: Epsom salt and baking soda are commonly available from pharmacies or supermarkets. Calcium chloride is often sold by home-brewing suppliers. Always choose food-grade products.
Is this safe for my espresso machine?: The calculator shows corrosion and scale risk. Very pure water can corrode metal, while very hard water creates deposits. SCA and Barista Hustle profiles balance equipment life and flavour.
# Why should I not use tap water directly?
Tap water changes by city and season. Chlorine, scale, or unbalanced minerals can mute specialty coffee and damage boilers. Mineralising distilled water gives repeatable results.| SCA Coffee Water Calculator | Minimum | Target | Maximum |
|---|---|---|---|
| GH | 50 mg/L | 68 mg/L | 175 mg/L |
| KH | 40 mg/L | 40 mg/L | 70 mg/L |
| pH | 6.5 | 7.0 | 7.5 |
| TDS | 75 mg/L | 150 mg/L | 250 mg/L |
# Where can I get the mineral salts?
Epsom salt and baking soda are commonly available from pharmacies or supermarkets. Calcium chloride is often sold by home-brewing suppliers. Always choose food-grade products.- Choose your target profile: Select SCA Ideal, Barista Hustle, Hendon, Melbourne, or create a custom profile with your own GH and KH values.
- Enter the final volume: Enter how many litres you want to mineralise. The calculator adjusts the concentrate doses for that exact volume.
- Add concentrates and top up: Use a precision syringe to add the indicated amounts, then fill the container to the final volume with distilled water.
# Is this safe for my espresso machine?
The calculator shows corrosion and scale risk. Very pure water can corrode metal, while very hard water creates deposits. SCA and Barista Hustle profiles balance equipment life and flavour.Get a pure base water
Use distilled, demineralised, or reverse-osmosis water. Starting near zero dissolved solids gives you full control.
# Prepare concentrate bottles
Dissolve each salt separately in 100 ml of distilled water using the recommended Epsom salt, calcium chloride, and bicarbonate amounts. 68 mg/L GH
40 mg/L KH
150 mg/L TDS