Misc addition
Chalk (Calcium Carbonate)
Spec sheet The maker publishes these figures for this exact product.
- Type
- Alkali
- Added at
- mash
- Form
- powder
- Formula
- CaCO₃
- Concentration
- sold as the pure compound
- Typical dose
- 0.5–2 g/L of mash water, with low confidence
- Timing
- Traditionally stirred into the mash; predose the water only if it is carbonated.
Before you use it
Chalk is barely soluble in mash-strength water — much of what you weigh out sits in the tun as grit and never reacts, so the real pH shift is often a fraction of what a calculator predicts. Prefer baking soda or slaked lime, or dissolve chalk under CO₂ pressure first.
Description
The classic textbook alkali for dark beers, offering calcium and carbonate together. In practice it is the least dependable pH tool in the cupboard and is best treated as a last resort.