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HTH Plus Granule Cal-Shock 25 lb. capacity
HTH Plus Granule Cal-Shock 25 lb. capacity
HTH Plus Granule Cal-Shock 25 lb. capacity

HTH Plus Granule Cal-Shock 25 lb. capacity

Made in America

Support American manufacturers + independent hardware retailers in one purchase.

A 25 lb supply of granular pool shock that clears cloudy water and keeps algae and bacteria in check all season.
Hth MPN 52057
Sold Locally Only

This product isn’t sold on our website — see your local hardware store.

In-Store Exclusive

This one's worth the trip to the store.

This Hth item is one you'll find in stores rather than online — and that's often the better way to buy. In store you get the genuine article, full manufacturer warranty, and real advice from someone who's actually handled it — no counterfeits, no gray-market resellers.

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About Product Overview

HTH Cal-Shock Plus is a granular pool shock made for restoring clarity after heavy pool use, a storm, or a long stretch without treatment. This 25 lb container is sized for pool owners who need enough product on hand to handle multiple shock treatments through the swim season, rather than picking up small bags every few weeks.

As a calcium hypochlorite shock, it works fast to knock down algae, bacteria, and the buildup that leaves water cloudy or gives off that strong chlorine smell (which is usually a sign of contaminants, not too much chlorine). It's a straightforward, no-frills product for anyone maintaining a residential pool who wants a reliable shock treatment without guessing at dosing every time.

  • Brand: HTH
  • Sub-brand: Cal-Shock Plus
  • Product form: Granule
  • Container size: 25 lb
  • Use: Residential pool maintenance
  • Made in the USA

The Details Specifications

Ships Ground Travels by ground for safe handling — common for items with a lithium battery, aerosol, or liquid inside. Nothing extra to do on your end; it simply ships by truck instead of by air.
Non-Returnable This product cannot be returned. All sales final.
Brand Hth
Model / MPN 52057
UPC 073187520579
Weight 28 lbs
Country of Origin USA
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
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