Sharpen the hops. Build your water.
Gypsum (calcium sulphate, CaSO₄) is the go-to salt for adding calcium and sulphate to soft brewing water. It lowers mash pH, adds permanent hardness, and brings out a crisp, dry, accentuated hop bitterness — the classic addition for IPAs, pale ales and British styles.
What it does
- Adds calcium — aids mash pH, protein break, beer stability and yeast health
- Adds sulphate — accentuates hop bitterness, drier finish
- Builds permanent hardness in soft water
Target levels
Aim for calcium around 50–150 mg/L. Sulphate is typically 10–50 mg/L for pilsners/light beers, 30–70 mg/L for ales, and pushed to 100–500 mg/L for assertively hoppy styles. The sulphate-to-chloride ratio steers the balance: above 1 leans hoppy, around 1 is balanced, below 1 leans malty.
Use a water tool (BeerSmith, Brewfather, RAPT) to calculate exact additions — usually only a few grams are needed.
For maltier water, pair with Calcium Chloride · Weigh accurately with our pocket scales · See all Cleaning & Ingredients
Specifications
| Compound | Calcium sulphate (CaSO₄) |
| Effect | Lowers mash pH; adds Ca + sulphate |
| Best for | Hoppy and British-style beers |
| Pack size | 500 g |