Sold in 100 g packs
Also known as Epsom salt
Lowers ph by a small amountEpsom is used to add sulfate and magnesium ions to brewing water. It is often used at half the levels of Gypsum. 1 gram in 1 gallon changes the salt levels by 103 ppm sulfate, 26 ppm Magnesium and adds 108 ppm to the hardness.
Can be used to add sulphate 'crispness' to hop bitterness