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In The Swim

In The Swim Pool Shock – 68% Cal-Hypo Granular Sanitizer for Crystal Clear Water – Defends Against Bacteria, Algae, and Microorganisms - 50 Pounds

    • Based on 14,628 reviews
Condition: New
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$264.99 Why this price?
Holiday Deal · 9% off was $289.99

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Availability: In Stock.
Fulfilled by In The Swim Pool Supplies
Arrives Saturday, Dec 28
Order within 4 hours and 14 minutes
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Style: Bucket


Size: 50 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: 50 Pounds


Item Form: Granular


Product Benefits: Contaminants


Unit Count: 800 Ounce


Product Benefits: Contaminants


Item Form: Granular


Item Weight: 50 Pounds


Brand Name: In The Swim


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Dec 28

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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  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
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  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Good stuff
Style: Bag Size: 24 x 1 Pound
My pool was starting to get algae and the algaecide I use requires a certain balance of chlorine PPM, and PH to be effective. I only had one bottle of liquid chlorine so I put that in and two pounds of shock, broadcast by hand. two hours later I added two cups of acid. After two more hours I added the algaecide that uses the chlorine in getting rid of the acid. Next morning, no algae and, as the description of the product mentioned, crystal clear water. As for the shock, it dissolved quickly, and unlike other shocks or powdered chlorine, all of it was dissolved and none of it was floating on the surface. ... show more
Reviewed in the United States on September 4, 2024 by JR 44308
    • Cheapest way to Chlorinate and add Calcium
Style: Bag Size: 24 x 1 Pound
As long as you are NOT paying shipping expenses (have Amazon Prime), this is the cheapest way to add chlorine to your pool, AND it adds calcium, AND you are not raising Cyanuric Acid (CYA), which should never exceed "30" for a residential pool. This product WILL also stabilize and raise pH, so you can buy less bicarbonate and reduce pH fluctuation. This product is a NO brainer as the best cheap source of chlorine for ANY pool (unless you do not want to increase water hardness (calcium) ). Stable at a minimum of 65% cholorine for well over 1 year, it does not go bad like liquid chlorine, which loses 1/2% + concentration per month! By the time you buy that liquid chlorine, it has probably already degraded a couple percent. The production date on the liquid chlorine is usually at least 50 days old. Learn to read the production date on liquid chlorine sold at HD or Lowe's and do not buy if it is old. The first digits are the year, the next set of digits is the day of the year. For example, a stamp that begins ...20366 will be December 31, 2020. NEVER toss powdered chemicals into pool unless they are pure chlorine. Powdered chemicals just sink and do who knows what to your pool surface. Always mix first in 5 gal bucket, stir, then add to water. I do this a couple times to fully dissolve the calcium. OF COURSE the water will go cloudy - it is *Calcium* HypoChlorite, but the cloudiness only lasts a short time. Most pools do not have enough calcium hardness - I keep mine well above 400 so I can keep the pH low for better chlorine efficacy. This product also avoids the cost of separately buying a calcium enhancer for the pool. Because it has no stabilizer it will not raise your CYA. Final point : Focus on maintaining LSI. This keeps the water from being corrosive or depositing calcium on the surface. I recommend the free Orenda app. Plus -- unlike liquid chlorine, this does not make the water taste salty, is easy to store, is stable, adds hardness, is cheaper source of Chlorine, does NOT add CYA! Minus -- mixing it up before adding to pool takes a couple minutes you have to be careful to avoid splashing, which will ruin your clothes. You also have to cut the packet with a knife or scissors and avoid spilling any. Highly recommended ... show more
Reviewed in the United States on April 3, 2021 by LJacobs
    • works great
Style: Bucket Size: 25 Pound
keeps pool clean
Reviewed in the United States on November 12, 2024 by Tawny
    • Cheaper to buy in bulk.
Style: Bucket Size: 25 Pound
Buying in bulk is cheaper than multiple single punches. The container comes with a measured cup.
Reviewed in the United States on April 10, 2024 by K.
    • Works Great
Style: Bucket Size: 25 Pound
This product cures the pink allege I had in my pool. The water is crystal clear and I will always have this product to keep the water healthy.
Reviewed in the United States on October 9, 2024 by Ronald Dodds
    • WORKS GREAT
Style: Bucket Size: 25 Pound
WORKED ON MY MESS OF A POOL WITH GREEN WATER
Reviewed in the United States on November 2, 2024 by Amazon Customer
    • Excellent product at a more reasonable cost
Style: Bucket Size: 50 Pound
This product is similar to shock sold by the large national chains but it comes at a much better cost.
Reviewed in the United States on November 13, 2024 by J
    • Great product
Style: Bag Size: 12 x 1 Pound
Easy to use and works as advertised.
Reviewed in the United States on September 29, 2024 by sjwallac

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