Sodium Bisulfate — Frequently Asked Questions

Because the hazard moves from the whole supply chain to the point of use. Sulphuric acid requires bunded storage, acid-resistant pumps, specialist transport and trained handling, and a spill is a serious incident. Sodium bisulfate delivers comparable acidity as a dry, non-fuming solid shipped in sacks and dosed by hand or screw feeder, and a spill is swept up.

Strongly acidic, around pH 1 in concentrated solution, because the salt retains one acidic proton per molecule from the partial neutralisation of sulphuric acid. It is a genuine strong acid in use and is corrosive to skin and eyes; the advantage is in handling and transport, not in reduced chemical aggressiveness once dissolved.

To lower pH and total alkalinity. Pool water drifts alkaline as carbon dioxide is lost and as chlorine products are added, and high pH reduces chlorine effectiveness and causes scaling and cloudy water. Sodium bisulfate corrects it without the handling risks of muriatic acid, which is why it is the usual choice for domestic and light commercial pools.

Yes, sodium bisulfate and sodium hydrogen sulfate are the same compound, NaHSO4, CAS 7681-38-1. It is also sold under names such as dry acid and pH minus in the pool trade. The CAS number is the reliable identifier when specifying.