Super Shockwave 73% Cal Hypo Granular Pool Shock, 1 lb Bag, 25252

Super Shockwave is calcium hypochlorite shock at 73%, with 70% available chlorine. It is the same granular cal hypo the industry runs on, at the top of the strength range: more chlorine and less inert filler in every pound than a 68% bag, so a bag raises the chlorine a little further and leaves a little less calcium behind. This listing is 1 lb bag.

How to use it

One bag per 10,000 gallons is the routine weekly shock. Add it in the evening with the pump running, broadcasting it across the deep end, and brush any granules off the floor so nothing sits on the surface. For a vinyl liner, pre-dissolve the bag in a bucket of water first and pour that in. On green or cloudy water, use two to three bags per 10,000 gallons, per the label, and repeat until the water holds chlorine overnight.

Swim wait

Chlorine shock raises free chlorine well above the normal 1 to 3 ppm, so stay out until it tests back to a safe level, typically 4 ppm or below. That is usually overnight to 24 hours. Test before you swim rather than counting the hours.

Handle it like the oxidizer it is

Never mix cal hypo with trichlor tablets or any other chemical, and always add chemical to water, never water to chemical. Store it cool, dry and sealed, away from acids and from non-chlorine shock. Bags beat buckets here: a pre-measured bag means no scoop, no dust on your hands and nothing to bleach your clothes.