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In The Swim

In The Swim Pool Shock - 68% Cal-Hypo Granular Sanitizer - 12 x 1 Pound

  • Based on 16,304 reviews
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Availability: In Stock.
Fulfilled by In The Swim Pool Supplies
Arrives Tuesday, Oct 27
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Style: Shock


Size: 12 x 1 Pound


Features

  • Fast-Acting Algae Control: Calcium Hypochlorite (Cal-Hypo) is an effective non-stabilized chlorine shock treatment, ideal for routine maintenance in your swimming pool
  • Versatile Use: Suitable for above ground or in-ground swimming pools, spas, and hot tubs; Pre-dissolve or dilute to avoid bleaching the liner
  • High Chlorine Content: 65% available chlorine, provides powerful sanitization for crystal-clear water
  • Easy Application: Pre-dissolve or dilute to avoid bleaching swimming pool liners; Spread granules in the deepest part of the pool; Brush if needed
  • Dosage: Use 1 Pound per 10,000 gallons weekly to maintain 5-10 ppm chlorine levels

Description

Get your pool swim-ready with the In The Swim Chemical Value Kit—a powerful bundle of essentials designed to keep your water balanced all summer long. Keep your pool crystal clear all season with slow-dissolving 3-Inch Chlorine Tablets that deliver powerful, long-lasting sanitization and UV protection—ideal for floaters and feeders. Maintain a pristine pool with Super Algaecide—keeping your water safe to swim in right away and gentle on your eyes and nose. Alkalinity Increaser features a granular formula that raises alkalinity, stabilizes pH, and ensures clear, safe water for pools, spas, and hot tubs. Cal-Hypo Pool Shock 3 Inch Chlorine Tablets Alkalinity Increaser pH Increaser pH Reducer

Brand: In The Swim


Item Weight: 13.1 pounds


Item Form: Granular


Product Benefits: Kills Bacteria, Maintains Clean Sanitized Water


Number of Packs: 12


Brand Name: In The Swim


Number of Packs: 12


Number of Items: 12


Unit Count: 192 Ounce


Manufacturer: In The Swim Discount Pool Supplies


Model Number: 25235 12X1


Manufacturer Part Number: 25235 12X1


Item Form: Granular


Product Benefits: Kills Bacteria, Maintains Clean Sanitized Water


Item Weight: 13.1 pounds


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Oct 27

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Top Amazon Reviews

    • Quality product
Style: Shock Size: 12 x 1 Pound
Price is fair and it's a effective item. My pool is about 16000 gallons and 1 bag a week works fine unless we get a lot of rain. Don't be concerned with the quality.
Reviewed in the United States on August 25, 2026 by Angela pilot
    • Quality product
Style: Shock Size: 12 x 1 Pound
Good price, I shock amount compared to others. I am very quick Delivery.
Reviewed in the United States on August 2, 2026 by ANNDEES
    • Good stuff
Style: Shock Size: 12 x 1 Pound
Used this stuff for the last two years. The trick is to dilute it in warm or hot water and let sit for about ten minutes then stir it with a stick then pour. It will get cloudy for about one to two days depending on how much you used. I like the cloudiness because I can see the chlorine circulation.
Reviewed in the United States on June 26, 2026 by Jimmy the Weasel
    • Reasonable product, economical, not as good as premium product
Style: Shock Size: 12 x 1 Pound
Does the job reasonably but not as good as local pool store product. Tends to take long to dissipate in the pool. Needs more product to raise chlorine level
Reviewed in the United States on August 17, 2026 by George/Princeton
    • Does the trick!
Style: Shock Size: 12 x 1 Pound
Great Pool shock fantastic Product
Reviewed in the United States on August 17, 2026 by Steve
    • A pool must have
Style: Shock Size: 12 x 1 Pound
Works great. We depend on it every year. It clears up water completely very wuickly.
Reviewed in the United States on September 2, 2026 by Michelle Palmer
    • Better price than shopping at the store stores
Style: Shock Size: 12 x 1 Pound
This works just like any other 1 pound bag of shock. I have a 20 foot round above pool, waterline is about 4 feet tall. I decided to purchase online because it is a little less expensive and more convenient than going to the store. I believe if this is on subscription you get an additional discount. I may go through one bag every 10 days and that’s mainly because my pool water gets warm because it’s in the sunlight the entire day. ... show more
Reviewed in the United States on August 1, 2026 by Erin LiDonni
    • Great product!
Style: Shock Size: 6 X 1 Pound
Works great for the pool!
Reviewed in the United States on September 3, 2026 by Roxann Johnson

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