Robelle 16-Pound Premium Pool Calcium Up — Calcium Hardness Increaser

Robelle 16-Pound Premium Pool Calcium Up is a dry granular formula designed to raise calcium hardness in pool water. By lifting the total hardness, it supports a stable balance that helps protect surfaces and equipment as water circulates.

Choosing the right hardness helps in different pool types. For vinyl pools, the recommended range is 200 to 300 ppm, while tile and exposed aggregate swim areas often sit between 200 and 400 ppm. Marcite, fiberglass, or painted surfaces typically operate best around 250 to 400 ppm. Regular testing with a trusted test kit guides when a treatment is needed.

Key benefits you may notice

• Rapidly increases total hardness when added as directed
• Helps prevent corrosion or etching of pool surfaces when hardness is within the target range
• Supports the ideal calcium hardness range of about 200 to 400 ppm across common pool types
• Eight ounces of the product can raise hardness by about 10 ppm in a 5,000 gallon volume
• Preventing staining and surface wear is associated with balanced hardness
• Addresses typical issues that occur when calcium hardness is too low

How to use and dosing guidance

Begin with a reliable water test to confirm the current calcium hardness. If the result is below the target range, prepare a solution by placing up to 2 pounds of the product into a plastic bucket filled with pool water. Slowly pour the solution around the pool perimeter while the circulation system operates.

• In a 10,000 gallon pool, do not add more than 10 pounds during any 2 hour period
• Follow the included chart to match quantity to your pool size and current levels
• Disperse gradually to avoid localized concentrations and ensure even distribution

In day to day use, homeowners notice smoother water balance after a routine check and adjust. The product works best when used as part of regular water testing and maintenance, and it is compatible with standard circulating systems.

Note that this product is intended as a water treatment aid and is not a guarantee of results. Benefits occur as part of maintaining balanced hardness when used as directed.