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Calcium Sulfate Gypsum 2 oz. for Home Brew

Calcium by Home Brew Ohio

Price
$7.06

What the brand says

Calcium sulfate is used to add permanent hardness (calcium ions) to brewing water. 1 gram in 1 gallon changes the salt levels by 61.5 ppm calcium, 147.5 ppm sulfate and adds 153.5 ppm to the hardness.