In The Swim Pool Shock – 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water – Defends Against Bacteria, Algae, and Microorganisms - 12 X 1 Pound
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Availability:
In Stock.
Arrives
Thursday, Mar 12
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
Brand: In The Swim
Item Weight: 13.1 Pounds
Item Form: Granular
Product Benefits: Kills Bacteria, Maintains Clean Sanitized Water
Number of Items: 12
Brand: In The Swim
Item Weight: 13.1 Pounds
Item Form: Granular
Product Benefits: Kills Bacteria, Maintains Clean Sanitized Water
Number of Items: 12
Unit Count: 192 Ounce
Product Dimensions: 10.8 x 9.9 x 5.3 inches
Item Weight: 13.1 pounds
Manufacturer: In The Swim Discount Pool Supplies
Item model number: 25235 12X1
Is Discontinued By Manufacturer: No
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Thursday, Mar 12
This item is non-returnable:
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Style: Shock
Size: 25 Pound
I’ve always been happy with In The Swim pool products and this is no exception. This along with a stabilizer keeps my chlorine levels in check. Tablets are made strong enough so that there is minimal breakage. They last a long time without breaking down.
Reviewed in the United States on February 26, 2026 by Jeff
Style: Shock
Size: 24 x 1 Pound
Good product and good price
Reviewed in the United States on February 20, 2026 by Lauri Brown
Style: Shock
Size: 24 x 1 Pound
OH BABY, worked as expected.
Reviewed in the United States on March 1, 2026 by Buyer
Style: Shock
Size: 24 x 1 Pound
Good product at a good price
Reviewed in the United States on January 23, 2026 by felixrangel
Style: Shock
Size: 12 x 1 Pound
I picked up this pool shock specifically to keep on hand for emergency situations rather than for pool maintenance. My goal was to have a reliable, long‑lasting sanitizer I could mix with water if needed, and this product fits that purpose well so far. The individually packaged 1‑pound bags make storage simple, and the high concentration means a little goes a long way. It seems durable and stable enough to keep on the shelf until I need it, which is exactly what I was looking for. Since I’m not using it in a pool, I can’t speak to its performance there, but as an emergency‑preparedness item, it’s been a solid addition. I’m giving it four stars mainly because I haven’t had to rely on it in a real emergency yet, so long‑term effectiveness is still something I can’t fully judge. Overall, it’s a practical product to have on hand, and it gives me some peace of mind knowing I have another option if I ever need to sanitize water quickly.
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Reviewed in the United States on March 1, 2026 by Paul G.
Style: Shock
Size: 24 x 1 Pound
The media could not be loaded. Get ready for **a shocking experience**—the clean kind! In this episode, **Papa Knows Stuff** tackles a grimy, dull, and cloudy pool and transforms it into a sparkling blue beauty using a **powerful pool shock treatment**. Watch the full **before and after pool transformation**, with tips, tricks, and satisfying footage that shows the real magic of a well-done pool shock. Whether you're a first-time pool owner or a seasoned backyard pro, this video breaks down everything you need to know about shocking your pool the right way. Papa walks you through the process step-by-step: checking the chlorine levels, balancing the pH, applying the pool shock, and letting it work overnight. The results? **Crystal-clear water that’s ready for summer fun!** 📌 **What You'll Learn & See in This Video:** * Why and when you should **shock your pool** * How to apply granular or liquid pool shock safely * The importance of circulation and timing * Satisfying before and after pool visuals * Tips on preventing algae, cloudiness, and odors * A side-by-side comparison showing real results in under 24 hours ⚠️ **Bonus Safety Tips:** * How to protect yourself when handling pool chemicals * Why shocking at night or in low sunlight makes a difference * How long to wait before swimming after a shock treatment
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Reviewed in the United States on May 9, 2025 by PapaKnowsStuff
Style: Shock
Size: 12 x 1 Pound
Have purchased this last year and it worked super. Decided while it was on sale to take advantage of the discount. Will order from this seller again.
Reviewed in the United States on January 16, 2026 by Pat H
Style: Shock
Size: 12 x 1 Pound
This is the best shock on the market in my opinion and this is a very good price for 12.
Reviewed in the United States on January 4, 2026 by Ladybugs