Calcium Sulfate (a.k.a gypsum) – an important mineral for its effect on mash and lowering wort pH. Used to harden soft water when brewing ales and bitters.
Calcium Sulfate causes permanent hardness because it doesn’t get removed during the boil. Calcium Sulfate is believed to suppress harshness and astringent flavours therefore allows brewers to use larger amounts of hops without extracting undesirable harshness from other components of the hop. Great addition to extra hoppy beers. Calcium Sulfate shouldn’t be overused though, it can create harsh tastes and impact on other aspects of the brew.
Depending on water hardness use as needed.