POWERFUL NON-CHLORINE SHOCK IS LONG-LASTING AND DISSOLVES COMPLETELY. Compare to Leisure Time®, Bioguard®, Guardex®, and Sun®. Spa Shock should be used weekly to oxidize organic contaminants, reduce chlorine odor and increase water clarity. Dosage: 2 oz. (1/4 cup) per 500 gallons weekly, or more often for heavy bather loads. Great for use with mineral stick systems Active ingredient: Persulphate compound.
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