Proper calcium hardness is essential for protecting your pool’s structure and equipment. When calcium levels drop too low, pool water becomes aggressive—pulling minerals from plaster, grout, heaters, and metal components. Over time, this leads to surface etching, staining, corrosion, and premature equipment wear. GLB Calcium Hardness Up (8 lb) is a fast-dissolving calcium increaser designed to quickly raise calcium hardness levels and restore proper water balance.

Formulated for residential pools and spas, this product helps stabilize water chemistry, protect pool finishes, and extend the life of heaters, pumps, and plumbing. It dissolves easily when applied correctly and works with all pool types and sanitizer systems.

This is a true pool-industry calcium hardness increaser—not a generic mineral additive.

Why Calcium Hardness Matters in Pool Water

Calcium hardness plays a critical role in maintaining balanced, non-corrosive pool water. Low calcium levels cause water to become “hungry,” leading it to leach minerals from pool surfaces and equipment.

Low calcium hardness can result in:

• Plaster and concrete surface etching

• Grout and tile deterioration

• Corrosion of heaters and metal components

• Cloudy water after chemical adjustments

• Reduced overall pool longevity

Raising calcium hardness to the proper range helps protect your investment and keeps your pool water stable and predictable.

Fast-Dissolving Formula for Reliable Results

GLB Calcium Hardness Up is engineered to dissolve efficiently when added according to label directions. It allows for controlled calcium increases without introducing unnecessary byproducts that can complicate water chemistry.

Once properly distributed, it helps bring calcium levels into the recommended range for plaster, concrete, vinyl, and fiberglass pools.

When to Use GLB Calcium Hardness Up

• Calcium hardness levels test below the recommended range

• New plaster or concrete pool start-ups

• After large water replacements or drain/refills

• To prevent etching, corrosion, or surface damage

• When balancing water after aggressive chemical corrections

Product Specifications

Application Notes

Always test water before adjusting calcium hardness. Add GLB Calcium Hardness Up according to label directions, pre-dissolving if required, and circulate water thoroughly after application. Avoid adding large amounts at once to prevent clouding.

Buy with Confidence from Benchmark Pool Supply

When you purchase GLB Calcium Hardness Up – 8 lb from Benchmark Pool Supply, you’re buying from pool professionals who understand water chemistry—not just chemical labels.

You can expect:

• Proven, pool-industry chemical products

• Reliable inventory and fast fulfillment

• Knowledgeable support from pool experts

• Products trusted by service technicians

Balanced water protects everything it touches—and calcium hardness is a key part of that balance.