Description

FreshWater Concentrated Chlorinating Granules is the primary sanitizer for spas running on a chlorine water care program — and the periodic shock product for spas running on FreshWater Salt System, Hot Spring ACE, or Ag+ Silver Ion programs. Active ingredient: sodium dichloro-s-triazinetrione (dichlor), a fast-dissolving, pH-neutral form of chlorine designed specifically for hot tubs.

This is the 3.5 lb container — the size most chlorine-system owners settle on after their first refill. A 3.5 lb container handles roughly six months of routine sanitation for a typical 400-gallon spa with normal bather load, or about three months of heavy use. For lower-volume use cases or first-time buyers, the 2 lb container is a smaller starter size in the same product line.

Why dichlor specifically (versus other chlorine forms): standard pool chlorines like calcium hypochlorite and trichlor are formulated for outdoor pools and will damage spa equipment. Calcium hypo raises calcium hardness over time, scaling heaters and salt cells. Trichlor is acidic, driving pH down with every dose and corroding spa interiors. Dichlor is pH-neutral, dissolves quickly without leaving residue, and stays clean in solution. It’s the right chemistry for the small water volume and high temperature of a residential spa.

Pro Tip: The target sanitizer residual for a chlorine-system spa is 2–3 ppm of free available chlorine. Higher than 5 ppm means you should not enter the spa — let the chlorine dissipate naturally before reuse. The most common new-owner mistake is dosing way over-target, then trying to soak before the chlorine drops back into range.
Brand

FreshWater®