First Choice Cal-Shock - Calcium Hypochlorite, 1 lb Bag

Excellent formulation for super-chlorination shock treatments. Quick dissolving, 68% Calcium Hypochlorite kills algae, bacteria and destroys organic contaminants.

Note: For every 10 ppm Free Chlorinne (FC) added by this Cal-Hypo product, it also increases Calcium Hardness (CH) by 8 ppm.