Building a water profile for pale ales
For a long time my pale ales had the right colour, the right bitterness on paper and still tasted flat, as if the hops were behind a curtain. Recipes, yeast and freshness of the hops all changed and the problem stayed. The one thing I had never touched was the water.
Start from a report
The local utility publishes an annual report. Mine is soft: very little calcium, almost no sulfate, low alkalinity. That is great for pilsner and not great for anything that should taste crisp and bitter. If your utility has no report, a cheap aquarium test kit gets you close enough for calcium and alkalinity.
| ppm | Tap water | Target for pale ale |
|---|---|---|
| Calcium | 18 | 80–120 |
| Sulfate | 12 | 150–250 |
| Chloride | 15 | 50–80 |
| Alkalinity (as CaCO₃) | 35 | under 50 |
Gypsum does most of the work
Gypsum (calcium sulfate) raises calcium and sulfate together. For 30 litres of total brewing water, 5 grams takes my water to roughly 70 ppm calcium and 150 ppm sulfate. A gram of calcium chloride on top softens the edge and helps body. I add the salts to the mash and the sparge water in proportion to the volume, not all at once to the mash.
A 0.1 g jewellery scale costs less than a bag of hops and it is the only way to weigh single grams reliably. Kitchen scales are not good enough here.
Check the mash pH
Salts also pull the mash pH down. With pale malts and my water the mash usually lands around 5.4 once the gypsum is in. Anywhere between 5.2 and 5.5 is fine; below that the beer gets thin and tart. I measure ten minutes into the mash with a sample cooled to room temperature. Strips are only good as a rough sanity check.
What changed
The first batch brewed this way was the same recipe as the one before it. The difference was obvious side by side: a drier finish, bitterness that stops instead of lingering, and hop aroma that finally came forward. Water will not fix a bad recipe, but it was the missing piece in mine.