Pool Mate Calcium Hardness Increaser for Pools, 8 lb — Fast-Dissolving Granular Calcium Chloride to Protect Surfaces

Pool Mate 8-Pounds Premium Calcium Hardness Increaser is a dry granular calcium chloride formula that safely raises your pool's calcium hardness to recommended levels.

Keeping the right calcium hardness helps protect pool surfaces and equipment from the damaging effects of soft water. This product is a fast-dissolving granular calcium chloride designed to bring total hardness into the ideal range for vinyl, tile, exposed aggregate, marcite, fiberglass and painted pools. Use a dependable test kit to measure current hardness, then follow the dosage chart and mixing instructions to avoid overcorrection.

How do I know when my pool needs calcium hardness added?

Test your pool water with a reliable calcium hardness test kit. If readings fall below the suggested ranges for your pool type, add Pool Mate Calcium Hardness Increaser in measured amounts and retest after circulation. Low hardness can contribute to faster wear of surfaces and corrosion of metal fittings.

• Vinyl pools: aim for 200–300 ppm
• Tile/exposed aggregate: aim for 200–400 ppm
• Marcite, fiberglass, painted: aim for 250–400 ppm
• Retest after full circulation and adjust in small increments

What is the correct way to add this granular calcium chloride?

Dissolve the measured granules in a plastic bucket prefilled with pool water before adding to the pool. Mix up to 2 pounds of product per 5-gallon bucket of water, then pour the solution slowly around the pool perimeter while the pump runs to distribute evenly. Never broadcast dry granules directly into the pool.

• Use only plastic buckets to dissolve product
• Mix up to 2 lb per 5-gallon bucket for safe dissolution
• Pour slowly around the pool with pump/circulation active
• Limit dosing to 10 lb per 10,000 gallons every two hours

How much will this 8-pound package change my pool’s hardness?

The product label provides a dosing chart, but a general rule is useful: 8 ounces of this calcium chloride will raise calcium hardness by about 10 ppm in 5,000 gallons of water. Use the chart for precise correction based on your pool volume, and add gradually to avoid overshooting the target range.

• 8 oz raises hardness ~10 ppm per 5,000 gallons
• Calculate pool volume to determine exact dose
• Add in increments and retest after circulation
• Follow the two-hour, 10 lb per 10,000 gallon safety guideline

Are there any safety or compatibility considerations?

Pool Mate calcium chloride is formulated for pools but must be handled with care. Wear gloves and eye protection when measuring and dissolving. Verify compatibility with your pool surface and follow manufacturer guidance for plaster and other sensitive finishes to prevent local concentration damage.

• Use protective gear when handling the dry product
• Always pre-dissolve in a plastic bucket to avoid direct contact
• Be cautious with rapid, concentrated additions near plaster or painted areas
• Store dry in a cool, sealed container away from moisture

Who is this for? Pool Mate 8-Pounds Premium Calcium Hardness Increaser is intended for pool owners and service professionals who need a reliable, fast-acting way to correct low calcium hardness. It’s suitable for a wide range of pool finishes and sizes when used according to the label instructions, making it a practical option for seasonal maintenance, post-drain refills, or whenever test results show calcium levels below the recommended target.