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

4.6 | 14,299 ratings

Price: 59.99

Last update: 09-10-2024

About this item

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.

Product information

Product Dimensions

10.8 x 9.9 x 5.3 inches

Item Weight

13.07 pounds

Manufacturer

In The Swim Discount Pool Supplies

ASIN

B002WKQ3IE

Item model number

25235 12X1

Customer Reviews

4.6 4.6 out of 5 stars 13,829 ratings

4.6 out of 5 stars

Best Sellers Rank

#149 in Patio, Lawn & Garden (See Top 100 in Patio, Lawn & Garden)
#8 in Swimming Pool Chlorine

Is Discontinued By Manufacturer

Top reviews from the United States

Texas Pops

Excellent price, good product, quick delivery.

Reviewed in the United States on May 9, 2024

Product works well. Does what it is intended to do.

MICHAEL J ASSAD

Inexpensive substitute pool shock treatment

Reviewed in the United States on May 29, 2024

Inexpensive substitute pool shock treatment compared to competitors. Works the same as others and gives great results.

Robert

Works Great, cleared water and killed algae.

Reviewed in the United States on May 7, 2024

Shock works great and the kids were able to swim a few hours later.

Cheaper to buy in bulk.

Reviewed in the United States on April 10, 2024

Buying in bulk is cheaper than multiple single punches. The container comes with a measured cup.

Jenny Goodlett

Pool supplies

Reviewed in the United States on May 12, 2024

Great product and ease of use.

RJacobs

Cheapest way to Chlorinate and add Calcium

Reviewed in the United States on April 3, 2021

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

Karonoz

Great price fast delivery

Reviewed in the United States on May 10, 2024

This gets my pool up and running every year. Got this at an amazing price

Kay Mayberry

pool shock

Reviewed in the United States on June 12, 2024

good quality

Best Sellers in

EASYTEST 7-Way Pool Test Strips, 150 Strips Water Chemical Testing for Hot tub and Spa, Accurate Test Bromine, Total Alkalini

4.5 14090

11.99

PoolRX+ pool unit 7.5k-20k gallons

4.5 5021

HTH 42052W Pool Care 3" Chlorine Tabs Advanced, Individually Wrapped Tablets - Swimming Pool Sanitizer with Clarifier & Algae

4.6 2880

44.74

AIPER Scuba SE Robotic Pool Cleaner, Cordless Robotic Pool Vacuum, Lasts up to 90 Mins, Ideal for Above Ground Pools, Automat

3.8 8793

149.99

Clorox® Pool&Spa™ Shock XTRABLUE®2, Kills Bacteria & Algae in Swimming Pools, Swim-Ready in 15 Minutes, (6-Pack)

4.7 2957

31.95

HTH 52037R Pool Care Shock Advanced, Swimming Pool Chemical - Cal Hypo Formula, Prevents Bacteria & Algae, Restores Crystal C

4.7 13347

57.78

In The Swim Pool Super Opening Chemical Start Up Kit - Above Ground and In-Ground Swimming Pools - Up to 35,000 Gallons

4.6 9233

57.99

Clorox® Pool&Spa™ Swimming Pool Algaecide and Clarifier, Prevents and Treats Pool Algae, Clears Water, 128 Fl Oz (Pack of 1)

4.5 12332

14.88