Just had a look at their site, which had this info on their water
Typical analysis shows Mg./L., Magnesium 23.5, Bicarbonate 176, Sodium 149, Potassium 3.4, Calcium 29.0, Sulphate 69.1, Iron .030, Chloride 202 and pH 7.2 - 8.3.
High Na and Cl and low Ca levels would make this a bugger of a...