What it is
Sulphate is a naturally occurring mineral dissolved from rocks such as gypsum. Most water contains some.
Where it comes from
Sulphate comes mainly from sulphate-bearing rocks in the aquifer. It can also come from mine drainage, industrial discharge and, in some areas, from the oxidation of natural sulphide minerals when groundwater levels fall.
Why it matters
Sulphate is not toxic. Above the guideline water tastes bitter and can cause a laxative effect, particularly in people who are not used to the supply, such as visitors. High sulphate also contributes to scale and can be corrosive to concrete.
What can be done about it
Sulphate is removed by reverse osmosis or by specialist ion exchange. Blending with another source is sometimes practical for a large supply. Pozzani will advise based on the level and how the water is used.
Information last reviewed 5 October 2026 by Pozzani Pure Water.