Residential Water Care

Spa Calcium Hardness Increaser

Brings calcium into ideal range

Natural Chemistry’s Spa Calcium Hardness Increaser is used to raise calcium hardness in spa water. Calcium hardness in spa water should be maintained between 150-250 ppm. Low calcium hardness levels could cause the spa water to be corrosive which may result in damage to the spa surface or equipment.

Spa Calcium Hardness Increaser™ Image
  • Brings calcium hardness level to an ideal range
  • Reduces cloudy water caused by low calcium levels
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Spa Calcium Hardness Increaser Instructions

Directions for use:

Read the entire label before using.

  1. Test spa water for calcium hardness level
  2. Compare test results to chart below to determine appropriate amount of product necessary to make adjustment.
  3. With the spa not in use and circulation pump operating, add required amount directly into spa water. Continue circulating water a minimum 20 minutes. Do not pre-dissolve this treatment as heat is generated when it contacts water.
  4. Retest and adjust if necessary.

Dosage Chart

All values are in grams

Spa Volume20ppm40ppm80ppm100ppm


Available Sizes

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