Calcium Sulphate (gypsum) - an important mineral for its effect on mash and wort pH. It is largely used to harden water when brewing ales and bitters.
Calcium Sulphate causes permanent hardness because it doesn't get removed by boiling. It is believed that sulphate suppresses harshness and astringent flavours which therefore allows brewers to use large amounts of hops without extracting undesirable harshness from other components of the hop. Calcium Sulphate shouldn't be overused though, as it can create a harsh taste and impact on other aspects of the brew.
Use as required depending on water hardness.
Net weight: 250g and 450gm