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In The Swim

In The Swim Alkalinity Increaser for Swimming Pools - Raises Alkalinity and Balances pH Levels in Your Swimming Pool Water - 100% Sodium Bicarbonate - 25 Pounds

  • Based on 2,313 reviews
Condition: New
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Availability: In Stock.
Fulfilled by In The Swim Pool Supplies
Arrives Sep 30 – Oct 2
Order within 8 hours and 39 minutes
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Style: Bucket


Size: 25 Pound


Features

  • In Swim Alkalinity Increaser maintains pH and chlorine levels.
  • Prevents pH swings, maintaining stable water chemistry.
  • High pH causes skin rashes; low pH stings eyes.
  • Ensures refreshing pool water, even in hot summers.
  • Maintain alkalinity at 90-120 ppm. Add 1.5 lbs per 10,000 gallons to increase by 10 ppm.

Brand: In The Swim


Item Weight: 27 Pounds


Item Form: Granular


Product Benefits: Alkalinity Increaser


UPC:


Brand: In The Swim


Item Weight: 27 Pounds


Item Form: Granular


Product Benefits: Alkalinity Increaser


UPC: 803354120857


Number of Items: 1


Unit Count: 400 Ounce


Product Dimensions: 12.5 x 10.4 x 8.9 inches


Item Weight: 27 pounds


Manufacturer: In The Swim Discount Pool Supplies


Item model number: Y7320


Is Discontinued By Manufacturer: No


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 30 – Oct 2

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.

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

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Good product
Style: Bucket Size: 25 Pound
Great price and does the job.
Reviewed in the United States on August 10, 2025 by Krista Thompson
    • Great value
Style: Bucket Size: 50 Pound
Why did you pick this product vs others?: Cheaper than the pool store and works just as well
Reviewed in the United States on July 14, 2025 by Bill Long
    • Delivery time
Style: Bucket Size: 50 Pound
Great product
Reviewed in the United States on August 30, 2025 by Amazon Customer
    • Works like a charm - as expected. Will keep this on hand and buy more as needed.
Style: Bucket Size: 25 Pound
Why did you pick this product vs others?: Newer pool and it's the first time using an alkalinity increaser. We've only used this once so far and it works as it should. Here's a bit of helpful math if needed: 2 cups = 1.5 lbs. The directions call for 1.5 lbs of product per 10K gallons of pool water to raise the alkalinity 10ppm. It's a 25 lbs container. ... show more
Reviewed in the United States on June 30, 2025 by Marlo Ann Myers
    • Great
Style: Bucket Size: 25 Pound
Better price than buying locally
Reviewed in the United States on April 15, 2025 by Jennifer K
    • Good alkalinity increaser
Style: Bucket Size: 25 Pound
Very easy to use to increase alkalinity in pool. Can get in 25 or 50 pounds. Starts to work as water circulates.
Reviewed in the United States on June 2, 2025 by Jessica Smith
    • Cheap.
Style: Bucket Size: 25 Pound
Cheap.
Reviewed in the United States on September 9, 2025 by dsutton
    • Clear water
Style: Bucket Size: 25 Pound
This item is key to keeping clear pool water!
Reviewed in the United States on September 1, 2025 by Richard Speruggia

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