Pool Acid 4 x 1 Gallon. (sold by box only).
22.64 25.52 $22.64 - $25.52
Muriatic Acid or Sulphuric Acid.
Muriatic Acid will control pH and will also clean concrete.
Sulphuric Acid will control pH and is FUME FREE, why choke yourself out every time you need to lower the pH?