SpaGuard pH Decreaser, Hot Tub Alkalinity Decreaser, 22oz

Sku: 42634BIO
(1 customer review)

Hot Tub Alkalinity Decreaser/pH Decreaser

Lowers the pH
Protects spa and equipment due to improper pH
Prevents cloudy water due to high pH
Balances water for bather comfort


SPAGUARD pH DECREASER is a Hot Tub Alkalinity Decreaser that lowers the pH of water in spas and hot tubs. The pH maintained at 7.2 to 7.6 (as measured by an accurate test method). SPAGUARD pH DECREASER is a dry granular product which is safer and easier to use than liquid acids.

MEASUREMENT AND DOSING: Use all level measurements. 1 level capful = 2 teaspoons = 0.5 ounce of this product. Note: Container cap provides convenient measure.


  1. Use and accurate test method to determine pH.
  2. Determine the required amount of SPAGUARD pH DECREASER needed to adjust the pH to maintain a reading of 7.2 to 7.6.
  3. Be sure the spas total alkalinity reading is at least 125 ppm (parts per million) before adding this product.
  4. With the pump operating, sprinkle this product into the water when the spa is not occupied. Let the pump circulate for 30 minutes to thoroughly mix the product. In units with aerators, the pump should be operating and the aerator off prior to application of the product.
  5. Reset pH and adjust as necessary.

NOTE: Additional product may be required based on system and other water balance parameters. Check pH and reapply if necessary. It is a good maintenance habit to test for acid/alkali demand periodically.

Reference numbers: CO505 L42634BIO 42634BIO

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1 review for SpaGuard pH Decreaser, Hot Tub Alkalinity Decreaser, 22oz







Reviewed by 01 customer(s)

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  • Rebekah

    Great for adjusting Total Alkalinity

    Used this to get that total alkalinity to where it’s supposed to be.

    August 28, 2023
    Verified Review

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