Pool Mate 8-Pounds Premium Calcium Hardness Increaser for Pools

Quick answer The Pool Mate 8-Pounds Premium Calcium Hardness scores 9.4/10 with us. Amazon owners rate it 4.7 out of 5 across 1,384 reviews, in line with the 4.6 average of the 16 pool balancers we track. It was listed at $16.68 on Amazon when we last checked in September 2026.

This is a dry granular product that increases the total hardness in pool water to the recommended range. Test for calcium hardness with a reliable test kit. The desired range for calcium hardness is as follows: Vinyl Pools: 200-300 ppm, Tile and Exposed Aggregate Pools: 200-400 ppm, Marcite, Fiberglass or Painted Pools: 250-400 ppm.

If the calcium hardness tests less than the desired range, add this product according to the included chart. Place this product into a plastic bucket already filled with swimming pool water. Do this in a ration of up to 2 pounds of product per approximate 5-gallon bucket of water.

Slowly pour this solution around the perimeter of the swimming pool while the circulating system is operating. In a 10,000 gallon pool, do not add more than 10 pounds of this product per 2 hour period.

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