Magnesium Sulphate (Epsom Salt)
Otherwise known as brewing salt, adjusts the ion content of your wort and enhances enzyme activity in your mash. It also lowers the pH by a small amount. This all aids to the desired flavour profile in your beer.
Use 1 gram per 1 gallon (3,8 litres).
Put 55g per 5 litres warm water and soak hands and feet for temporary pain relief after a long day’s brewing…