LOCAL DELIVERY OR IN-STORE PICKUP ONLY GLB Calcium Hardness Up (25 lb) is a professional-grade calcium increaser designed to raise calcium hardness levels in swimming pools. Proper calcium hardness is essential for protecting pool surfaces and equipment while maintaining balanced water chemistry. This fast-dissolving formula allows for controlled calcium adjustment without clouding water when used as directed. Low calcium hardness can cause aggressive water conditions that slowly etch plaster, weaken grout, and corrode metal components. Over time, this damage can shorten the life of pool finishes and equipment. Calcium Hardness Up helps restore proper balance, protecting your investment and improving overall water stability. This 25 lb container is ideal for residential pools and ongoing maintenance programs that require precise hardness control. Why Calcium Hardness Matters Calcium hardness plays a critical role in overall water balance. Why this matters: Protects plaster, tile, and concrete pool surfaces from etching Helps prevent corrosion of heaters, pumps, and metal fittings Supports stable water chemistry and balanced saturation levels Reduces long-term surface and equipment damage Improves overall pool longevity Maintaining proper calcium levels helps keep water balanced and prevents costly repairs caused by aggressive or corrosive water. Designed for Pool Water Chemistry Control GLB Calcium Hardness Up is formulated specifically for swimming pool use and is compatible with most pool types, including plaster, concrete, and tile pools. The granular formula dissolves efficiently when added according to manufacturer directions, allowing for even distribution throughout the pool. This product is commonly used after water dilution from rain or refill, startup of new plaster pools, or when routine testing shows low calcium hardness levels. Always test water chemistry before and after application to ensure accurate dosing. Easy Application for Maintenance & Startups Calcium Hardness Up is easy to apply and works quickly when properly dispersed. The product can be pre-dissolved in a bucket of pool water and poured evenly around the pool perimeter or added according to professional service procedures. Best practices include: Testing calcium hardness before dosing Adding product in stages to avoid overshooting target levels Circulating water continuously during application Re-testing after full circulation Proper application ensures effective results without water clarity issues. Product Specifications Specification Details Product Type Calcium hardness increaser Brand GLB Size 25 lb Application Raises calcium hardness Use Pool water chemistry balance Form Granular Condition New UPC 785336712147 Buy with Confidence from Benchmark Pool Supply When you purchase GLB Calcium Hardness Up from Benchmark Pool Supply, you’re choosing a trusted water chemistry product used by pool professionals. We stock essential balancing chemicals to help maintain safe, stable, and well-protected pool water. Benchmark Pool Supply is your reliable source for professional-grade pool chemicals and water care solutions.