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SpaGuard® Rapid-Dissolve Alkalinity Increaser Tabs 1.25 lb bottle 42661BIO, front label

SpaGuard® Rapid-Dissolve Alkalinity Increaser Tabs for Spas & Swim Spas, 1.25 lb 42661BIO

Regular price $15.99
Sale price Regular price

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Key Features & Benefits

Controls pH Bounce

Quickly raises total alkalinity to steady pH

Pre-Measured Tabs

Engineered for seamless compatibility with original mounting points for secure placement.2 tabs per 250 gallons raise alkalinity 30 ppm (per SpaGuard®)

Spas & Swim Spas

Labeled for use in spas and swim spas

Protects Equipment

Helps protect equipment from corrosion

1.25 lb Bottle

567 g of rapid-dissolve tablets

Genuine SpaGuard®

Manufactured for BioLab, Inc., part number 42661BIO

Product Overview

SpaGuard® Rapid-Dissolve Alkalinity Increaser Tabs raise total alkalinity in spas and swim spas without measuring granules. The label says they control pH bounce by quickly raising total alkalinity and help protect equipment from corrosion. The bottle holds 1.25 lb (567 g) of tablets.

SpaGuard® lists a dose of 2 tabs per 250 gallons (1,000 liters), as needed, to raise total alkalinity by 30 ppm. Test alkalinity first, add tablets for your spa's volume with the pump running, let the water circulate, and retest before adding more. Follow the full directions on the label.

The label carries the DANGER signal word: causes serious eye damage. Keep the bottle out of reach of children, avoid contact with eyes, read all precautions on the label before handling, and never mix it with other chemicals. These tabs are a water balancer and do not sanitize the spa. For granular dosing, SpaGuard® Total Alkalinity Increaser is the alternative.

    • 1. Test total alkalinity and pH.
    • 2. Dose: SpaGuard® lists 2 tabs per 250 gallons (1,000 liters), as needed, to raise total alkalinity by 30 ppm.
    • 3. With the pump running, add the tablets to the spa water.
    • 4. Let the water circulate, then retest before adding more. Follow the full label directions.
    • Signal word: DANGER. Causes serious eye damage.
    • Keep out of reach of children. Avoid contact with eyes.
    • Never mix with other chemicals. Read all precautions on the label.
    • Keep the lid closed and store in a cool, dry place.
  • Total alkalinity buffers pH. Bring alkalinity into the range your spa manufacturer recommends before adjusting pH, so pH stays steady between tests.

    • One 1.25 lb (567 g) bottle of SpaGuard® Rapid-Dissolve Alkalinity Increaser Tabs, part number 42661BIO

Frequently Asked Questions

  • They raise total alkalinity to control pH bounce and help protect spa equipment from corrosion.
  • SpaGuard® lists 2 tabs per 250 gallons (1,000 liters), as needed, to raise total alkalinity by 30 ppm. Follow the label.
  • Test first, add tablets for your spa's volume with the pump running, let the water circulate, then retest before adding more.
  • Yes. The label says for spas and swim spas.
  • They are pre-measured tablets, so there is no scooping. SpaGuard® Total Alkalinity Increaser is the granular option.
  • Raising alkalinity can nudge pH up. Retest pH once alkalinity is in range and adjust if needed.
  • The label carries the DANGER signal word: causes serious eye damage. Keep out of reach of children and read all label precautions.
  • No. They are a water balancer. Keep using your normal sanitizer.
  • 1.25 lb (567 g) net weight. Part number 42661BIO.

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