Spa Calcium Increaser

Raises Calcium Hardness in Spa/Hot Tub Water

Natural Chemistry’s Spa Calcium 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.

  • Raises calcium hardness in spa and hot tub water
  • Reduces cloudy water caused by low calcium levels
  • Low calcium hardness levels could cause the water to become corrosive, which may result in damage to the spa surface or equipment


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 spa circulating pump on high speed, 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 dry ounces

Spa Volume20ppm40ppm80ppm100ppm

  Printable version

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Material Safety Data Sheets

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