In The Swim Pool Shock  68% Cal-Hypo Granular Sanitizer for Crystal Clear Water  Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1
In The Swim Pool Shock  68% Cal-Hypo Granular Sanitizer for Crystal Clear Water  Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1
Hero image 0 of In The Swim Pool Shock 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1, 0 of 5

In The Swim Pool Shock 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1

4.5 stars out of 691 reviews
(4.5)|
691 ratings

Key item 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
  • Effective Sanitization: 68% Calcium Hypochlorite active ingredient kills bacteria, algae, and microorganisms
  • Economically Priced: Packaged in 1lb bags for convenient pool or spa shock treatment
  • Water Balance: Maintain pH 7.2-7.6, total alkalinity 60-120 ppm, and calcium hardness above 200 ppm for best results
  • Routine Maintenance: Shock treatment every 7 days or as necessary to prevent pool problems
Generated by AI
Current price is $99.99
Price when purchased online
  • Free shipping

How do you want your item?

How do you want your item?
Columbus, 43215
Arrives by Wed, Feb 4
|
Sold and shipped by In The SwimPro Seller
4.363213811420983 stars out of 5, based on 3012 seller reviews(4.4)
Report an issue with this seller
Return policy

About this item

Product details

Warranty

Warnings

Frequently bought together

In The Swim Pool Shock 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1 $99.99

In The Swim Pool Shock  68% Cal-Hypo Granular Sanitizer for Crystal Clear Water  Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1
current price $99.99

In The Swim Pool Shock 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water Defends Against Bacteria, Algae, and Microorganisms- 24 X 1 Pound 25266 2X12X1

4.5 out of 5 Stars. 691 reviews

Mainstays Plastic Pool Surface Skimmer $24.88

Mainstays Plastic Pool Surface Skimmer
current price $24.88

Mainstays Plastic Pool Surface Skimmer

4.2 out of 5 Stars. 198 reviews

U.S. Pool Supply 12" Deluxe Weighted Butterfly Pool Vacuum Head, Swivel Hose Connection, Pole Handle, Protection Bumper - Clean Debris Above Ground & In-Ground Swimming Pools, Spas – Vinyl Liner Safe $19.99

U.S. Pool Supply 12" Deluxe Weighted Butterfly Pool Vacuum Head, Swivel Hose Connection, Pole Handle, Protection Bumper - Clean Debris Above Ground & In-Ground Swimming Pools, Spas – Vinyl Liner Safe
current price $19.99

U.S. Pool Supply 12" Deluxe Weighted Butterfly Pool Vacuum Head, Swivel Hose Connection, Pole Handle, Protection Bumper - Clean Debris Above Ground & In-Ground Swimming Pools, Spas – Vinyl Liner Safe

4.2 out of 5 Stars. 36 reviews

Mainstays Small Pool & Spa Manual Debris Catcher in Plastic & Aluminum - Gray - 1.54 lb $34.97

Mainstays Small Pool & Spa Manual Debris Catcher in Plastic & Aluminum - Gray - 1.54 lb
current price $34.97

Mainstays Small Pool & Spa Manual Debris Catcher in Plastic & Aluminum - Gray - 1.54 lb

3.8 out of 5 Stars. 57 reviews
Current price is $179.83
Items may be delivered on different dates

Customer ratings & reviews

4.5 out of 5 stars
stars691 ratings580 reviews
How item rating is calculated

Reviews summary

Pros
  • : Made with high-grade materials and construction.
  • : Found to be cheaper than others.
Generated by AI

Customer images

Filtered and sorted results would be available on the new 'Customer ratings & reviews' page.
Sort by |

Showing 1-3 of 580 reviews

Sep 26, 2025
Hugh R.
5 out of 5 stars review

Seller Verified Purchase

Good Quality at a Good Price

I actually use this as my daily chlorine additive because I do not want to use any chlorine with stabilizer in it. Several years ago my pool was a mess because after years of using 3 inch tablets that had stabilizer in them, it was ridiculously high with stabilizer and that messed everything up. So now I only use pure chorine. I alternate between this and bleach and the pool is much easier to keep in balance. I very occasionally add stabilizer when needed.

Review from https://intheswim.com
Helpful?67BNB5L6C17L568435365
Jul 31, 2025
Michael
Item details
Size: 50 lbs
Sold and shipped byIn The Swim
5 out of 5 stars review

Verified Purchase

The lid is easy to open after figuring out how it opens. Comes with a nice plastic measuring cup with a handle. It was delivered to my house on time properly packaged. The price was pretty good compared to other stores. I have no complaints and would recommend this product.

Helpful?67BNB5L6C17L568435365
Apr 21, 2025
Jane D.
5 out of 5 stars review

Seller Verified Purchase

Effective treatment week after week!

We upgraded our above ground pool the summer that covid rocked the world. We have used nothing but In The Swim products from Day One and have enjoyed sparkling blue water with minimal problems I see others posting and seeking help for. The 1lb bags of pool shock are a “single serving”, no measuring or worrying about kids or pets getting into open bags of chemicals. An ounce (or 1lb) of prevention beats 5k gallons of green water!

Review from https://intheswim.com
Helpful?67BNB5L6C17L568435365