Also known as brewing salts, it is a mixture of Gypsum, Potassium Chloride and Epsom Salt. 1 tsp adds 1119 ppm per 5 gallons. For Pale Ales in the Burton on Trent style.
30g per 5 gallons will provide:
266 ppm Ca
63 ppm Mg
159 ppm Carbonate
631 ppm Sulfate