Rochefort (Saint-Rémy Abbey), Belgium. Moderately hard water with high residual alkalinity - suited to dark, roasty beers, with sulfate and chloride roughly in balance.
| Ion | ppm |
|---|---|
| Calcium (Ca²⁺) | 82 |
| Magnesium (Mg²⁺) | 10 |
| Sodium (Na⁺) | 6 |
| Chloride (Cl⁻) | 17 |
| Sulfate (SO₄²⁻) | 32 |
| Bicarbonate (HCO₃⁻) | 240 |
| Brewing numbers | |
|---|---|
| Total hardness (as CaCO₃) | 245.9 ppm |
| Alkalinity (as CaCO₃) | 196.8 ppm |
| Residual alkalinity (as CaCO₃) | 132.4 ppm |
| Sulfate-to-chloride ratio | 1.9:1 |
Salts to add to reverse-osmosis or distilled water, calculated by the BrewWaterSolver solver with the most common homebrew salts.
| Salt | 5 gal (18.9 L) | 20 L |
|---|---|---|
| Calcium chloride (CaCl₂) | 0.55 g | 0.58 g |
| Epsom salt (MgSO₄) | 1.59 g | 1.68 g |
| Chalk (CaCO₃) | 3.53 g | 3.74 g |
| Baking soda (NaHCO₃) | 0.21 g | 0.22 g |
The common salts reproduce every ion within 10%.
Chalk (CaCO₃) doesn't dissolve well directly in mash or sparge water without dissolved CO₂ - slurry it in carbonated water (e.g. sparkling water) before adding it, rather than mixing it into still water or sprinkling it in dry, or the calculated amount may not fully dissolve. How to dissolve chalk with CO₂
Stan Hieronymus, Brew Like a Monk (Brewers Publications, 2005) - Ca 82, Mg 10, Na 6, Cl 17, SO4 32, HCO3 240, as published in the book for Rochefort Abbey's brewing water. The book also notes the monastery makes no attempt to control mash pH given this water and instead corrects post-boil with a mineral acid.