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In The Swim Pool Shock – 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water – Defends Against Bacteria, Algae, and Microorganisms - 25 Pounds

  • Based on 13,629 reviews
Condition: New
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$159.99 Why this price?
Save $7.80 was $167.79

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Non-returnable due to hazmat safety reasons

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Availability: In Stock.
Fulfilled by In The Swim Pool Supplies

Arrives Sunday, May 26
Order within 17 hours and 42 minutes
Available payment plans shown during checkout

Style: Bucket


Size: 25 Pound


Features

  • Powerful chlorine shock treatment that is great for regular maintenance.
  • Quickly eliminates algae, bacteria, and other harmful contaminants from your pool water.
  • Main active ingredient is 68% Calcium Hypochlorite (Cal-Hypo) for quick sanitizing.
  • Dosage: 1 Pound per 10,000 gallons
  • Cal-Chlor granules can be used in swimming pools, spas and hot tubs. Must pre-dissolve/dilute to prevent bleaching of the liner.

Brand: In The Swim


Item Weight: 25 Pounds


Item Form: Granular


Product Benefits: Controls Algae


Product Dimensions: 13.2 x 13 x 12.2 inches


Item Weight: 25 pounds


Manufacturer: In The Swim Discount Pool Supplies


Item model number: 25237


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, May 26

This item is non-returnable:

Non-returnable due to hazmat safety reasons

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • High active chlorine and a great value
Style: Bucket Size: 25 Pound
I have a medium sized pool and tiles of paying over $200 for a bucket from Leslies. Check the active ingredients yourself. This is very close to the pool store brand and much cheaper. Does the job great.
Reviewed in the United States on March 31, 2024 by Thecaffeinated1

  • Works
Style: Bucket Size: 50 Pound
Worked fine. Better price
Reviewed in the United States on April 1, 2024 by paul hughes

  • Good Buy - Well Packaged
Style: Bag Size: 24 x 1 Pound
This chlorine shock works well. It comes in 1lb plastic bags that are easy to handle and will not break open on accident. When our chlorine levels drop, we sprinkle in a bag or two of this, using it in conjunction with our 3" tablets, and it quickly brings the chlorine count back into range. We've had good experiences with most in the swim products. ... show more
Reviewed in the United States on March 18, 2024 by Kevin

  • Product is great, shipping is not!
Style: Bucket Size: 50 Pound
The media could not be loaded. Product is great and competitively priced. Just be careful when opening the box cause the shipping companies don’t always take care of packages!
Reviewed in the United States on February 14, 2024 by Robert

  • Perfect for our pool!
Style: Bucket Size: 50 Pound
Great price compared to local
Reviewed in the United States on March 27, 2024 by Debras

  • This product really worked.
Style: Bucket Size: 25 Pound
This is the second time I have purchased this product and it really works! The first time I purchased it my pool was green! I tried everything and spent a fortune, still green, I watched a youtube video, and the influencer reccommended it so I decided to try it. I ended up using the whole bucket but finally a blue pool. I decided to buy a backup! ... show more
Reviewed in the United States on March 18, 2024 by Penelope Suozzi

  • Works Great!
Style: Bag Size: 6 X 1 Pound
I use this once a month along with the same brand chlorine tabs and my pool looks great! Easy to use and sprinkle throughout the pool and spa area. I let it work for a couple of days during swimming season before getting in it, then backwash after a week. I would recommend using this along with their chlorine tabs. ... show more
Reviewed in the United States on January 21, 2024 by Coach

  • Great product
Style: Bucket Size: 25 Pound
I have been using this now for the last 12 years never had any problems issues or concerns with it will continue to purchase in the future as needed.
Reviewed in the United States on March 26, 2024 by Nidia

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