Water recipe part 2

 Corrected input data for calcium( 11 instead if 1.1 ppm)

Based on Australian sparkling ale recipe,

water requirements:

Ca ≥ 50 ppm, Mg ≤ 10 ppm, Na ≤ 10 ppm, SO4 ≈ 75 ppm, Cl ≈ 50 ppm, HCO3 ≤ 10 ppm

if no salt addition, delta is as below:

Water recipe with salts added, based on 3L mash:

Overall report:

The delta

Gypsum calcium sulphate CaSO4 · 2H2O and calcium chloride correct calcium quite well.

Better to keep calcium and sodium below 100 ppm.

Sulphate enhance hop crisp bitterness, eg west coast style beers

Chloride enhance softnees, round mouthfeel, eg New England style

ie Sulphate to chloride ratio

This combination is not perfect, but quite close 

Slaked lime Ca(OH)2熟石灰 more stable and soluble than chalk CaCO3生石灰

CaCl2 鹽丹（做豆製品用，除濕）

Conclusion:

From bruhlosophy exBeeriment, not everyone can taste the difference. So major reason seems to adjust pH of mash for enzymes to convert starch to sugars, pH 5.2-5.5. 

Preferably use phosphoric acid to lower pH( more acidic), as it's neutral in flavours.

John Palmer on residual alkalinity & brewing water, Northern Brewer YouTube 

and yeast to ferment?

John Palmer water chemistry pdf