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Calcium Hardness Increaser | 42636BIO

Calcium Hardness Increaser | 42636BIO

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SpaGuard's Calcium Hardness Increaser is a convenient and effective granular formula for raising calcium hardness. By slowly increasing calcium levels, this product aids in avoiding scale build-up and cloudy water. Additionally, it helps protect equipment from corrosion, as the optimal calcium hardness level is between 200-400 ppm, and anything lower than 100 ppm can lead to corrosion.


  1. Utilize a reliable and precise test method to determine the calcium hardness of your water.
  2. Consult the provided chart and analyze your total calcium test results to determine the necessary amount of SpaGuard Calcium Hardness Increaser needed for adjusting the calcium levels. Maintain a reading of 100-200 ppm*.
  3. For spas on the BioGuard SoftSoak Program, adjust the calcium to maintain a reading of 200-300 ppm.
  4. Ensure the spa pump is running on high speed.
  5. Sprinkle the designated amount of SpaGuard Calcium Hardness Increaser directly into the spa water.
  6. Allow the pump to continue running for 30 minutes. There is no need to pre-dissolve the treatment, as it generates heat upon contact with water.
  7. Take care to measure the SpaGuard Calcium Hardness Increaser accurately. Inaccurate measuring can result in undesired calcium hardness levels.

*ppm: parts per million


1 tbsp per 100 gallons of water will raise hardness by 25 ppm.


Calcium Chloride
Sodium Chloride
Potassium Chloride

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