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Natural Chemistry Calcium Hardness Increaser 1.75 lbs
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Spa Calcium Hardness Increaser is used to raise calcium hardness in spa water. Calcium hardness in spa water should be maintained between 150-250ppm. Low calcium hardness levels could cause the spa water to be corrosive which may result in damage to the spa surface or equipment.

  • Brings calcium hardness level to an ideal range
  • Reduces cloudy water caused by low calcium levels
Natural Chemistry Calcium Hardness Increaser 1.75 lbs
$ 9.99 New Available online


* 1.75 lb container
Read entire label before using

1. Test spa water for calcium hardness level
2. Compare test results to chart below to determine appropriate amount of Spa Calcium Hardness Increaser necessary to make adjustments
3. With spa circulating pump on high speed, add required amount directly into spa water
4. Continue circulating water a minimum 20 minutes
5. Do not pre-dissolve this treatment as heat is generated when it contacts water
6. Retest and adjust if necessary 

Dosage Chart

All values are in dry ounces 

Spa Volume 20ppm 40ppm 80ppm 100ppm
200gal (760L) 1 1 1/2 3 1/4 4 1/4
400gal (1500L) 1 1/2 3 1/4 6 1/2 8 
800gal (3000L) 3 6 1/2 13 16

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Natural Chemistry Calcium Hardness Increaser 1.75 lbs

Code: natural-chemistry-04105
Usually Ships In 1-2 Business Days