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CLOROX Pool&Spa

Clorox® Pool&Spa™ Swimming Pool Calcium Hardness Increaser, Prevents Corrosion, Etching and Staining, 4LB (Pack of 1)

  • Based on 5,082 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Sep 7
Order within 18 hours and 18 minutes
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Size: 1 Count (Pack of 1)


Features

  • Prevents Corrosion, Etching, and Staining: With Clorox Pool&Spa Swimming Pool Calcium Hardness Increaser, you can safeguard your pool against corrosion, etching, and staining, ensuring its longevity and pristine appearance. Our product offers reliable protection, giving you peace of mind while you enjoy your pool.
  • Increases Low Total Hardness Levels: This product helps increase the low total hardness levels in swimming pool water, ensuring a balanced and stable environment for your pool. It restores water parameters to their ideal ranges.
  • Extends Equipment Life: Unbalanced water can cause a corrosive environment that damages your pool surfaces or equipment. This product prevents pool surface damage, reduces pool maintenance, extending the life of your pool's cleanliness.
  • Compatibility: Our Clorox Pool&Spa Swimming Pool Calcium Hardness Increaser is ideal for plaster pools and areas with soft water.
  • Clorox Pool App: Test like an expert anytime, anywhere with the Clorox Pool App. Solve common swimming pool problems and get personalized product and dosage recommendations.

Description

Clorox Pool&Spa Swimming Pool Calcium Hardness Increaser, Prevents Corrosion, Etching and Staining, 4LB (Pack of 1);12204CLX.

Brand: CLOROX Pool&Spa


Item Weight: 4 pounds


Item Form: Granular


Product Benefits: Staining Prevents,Corrosion,Prevents Corrosion


UPC:


Brand Name: CLOROX Pool&Spa


UPC: 810821023108


Global Trade Identification Number: 08


Number of Packs: 1


Number of Items: 1


Unit Count: 64 Ounce


Included Components: Includes 1 x Pool&Spa 12204CLX Calcium Hardness Increaser, 4 lb


Item Type Name: Calcium Hardness Increaser, 4 lb.


Manufacturer: Clorox Pool&Spa


Model Number: 12204CLX


Manufacturer Part Number: 12204CLX


Item Form: Granular


Product Benefits: Staining Prevents,Corrosion,Prevents Corrosion


Item Weight: 4 pounds


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Sep 7

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Easy Way to Balance Pool Water
Size: 1 Count (Pack of 1)
This calcium hardness increaser worked exactly as expected. It dissolved well, was easy to add to my pool, and helped bring my calcium hardness into the proper range without any issues. After using it, my pool water stayed balanced, and I felt confident knowing I was helping protect my pool surfaces and equipment. It's an excellent product that's simple to use and does what it promises. I would definitely purchase it again. ... show more
Reviewed in the United States on July 22, 2026 by Krista Goodwin
    • Best price I’ve found
Size: 1 Count (Pack of 1)
This stuff is about as basic a chemical as it gets. Calcium carbonate is simply used to raise the hardness of soft water to protect the spa’s metal pump and piping components. Don’t need high hardness, but our water runs 80-100 ppm so takes a bit of calcium to boost it after periodic top offs. Calcium ice melter would work but it’s kind of dirty so forced to buy these purified versions. Absolutely no benefit to buying a more expensive version. Buy the cheapest you can find. This one seemed reasonably cheap. ... show more
Reviewed in the United States on July 30, 2024 by ChemE_75
    • Protects the Vinyl Liner
Size: 1 Count (Pack of 1)
I use the Clorox Calcium hardness increaser to protect our vinyl pool liner. It dissolves quickly and is effective in increasing the transparency of the water and reducing algae blooms.
Reviewed in the United States on May 19, 2026 by Waln Brown
    • Pool and Spa Chemicals
Size: 1 Count (Pack of 1)
This stuff dissolves pretty fast and seems to work just fine for me
Reviewed in the United States on August 1, 2026 by Rick
    • Keep for you pool when you need it!
Size: 1 Count (Pack of 1)
Always get this instead of from our pool guy. Saves you money!
Reviewed in the United States on August 3, 2026 by Connie S.
    • Best solution
Size: 1 Count (Pack of 1)
Nothing bad can be said about this product. I have a small hot tub, 250 gallons, and sometimes it can be difficult to maintain balance but I find if I drip a few of these into a floating Bromine dispenser and set it to the lowest opening g it will last for weeks and keep the bromine level at the proper concentration. Value for the money is very good , highly recommended! ... show more
Reviewed in the United States on April 12, 2024 by Rob
    • For our hot tub
Size: 1 Count (Pack of 1)
Works well!
Reviewed in the United States on May 4, 2026 by Jason Y.
    • words as intended
Size: 1 Count (Pack of 1)
Worlds as intended!
Reviewed in the United States on May 11, 2026 by Brandy

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