Add 1 tsp to water prior to fermentation, to replicate the natural hard water supply when making English Ales etc. 1 tsp. of Epsom Salt (MgSO4) in 20 litres of water will increase concentration of (Mg++)ion 52ppm (SO4--)ion. 207ppm.
Potassium Metabisulphite (PMS) is used for sterilizing & stabilizing wine. CRUSHING: Use 50g - 75g per 100L of must to kill bacteria on the grapes PRIOR to adding yeast