When total alkalinity drops too low, pool water becomes difficult to manage. pH swings rapidly, chlorine efficiency suffers, and water can turn corrosive to surfaces and equipment. GLB Alkalinity Up 5 lb is a professional-grade alkalinity increaser designed to restore balance quickly and reliably, giving your pool the chemical stability it needs to stay clear, comfortable, and protected.

Total alkalinity acts as the foundation of water balance. Without it, even correctly adjusted pH and chlorine levels won’t stay in range for long. GLB Alkalinity Up raises alkalinity in a controlled, predictable way—making all other water chemistry easier to maintain.

This 5 lb size is ideal for smaller pools, spas, and routine touch-ups, or for homeowners who want precise control without buying bulk quantities.

Why Total Alkalinity Must Be Corrected First

Many ongoing pool problems trace back to low alkalinity. When alkalinity is unstable, pH becomes reactive and difficult to control, forcing repeated chemical adjustments that waste time and money.

Low alkalinity can cause:

• Rapid pH fluctuations

• Reduced chlorine effectiveness

• Corrosive water that etches plaster and damages heaters

• Eye and skin irritation

• Increased overall chemical demand

By correcting alkalinity first, GLB Alkalinity Up helps stabilize the entire water system instead of chasing symptoms.

How GLB Alkalinity Up Works

GLB Alkalinity Up is formulated with a high-purity alkalinity increaser that dissolves cleanly and raises total alkalinity without clouding water when used as directed. Once alkalinity is back in range, pH becomes far more stable and chlorine performs more efficiently.

This predictable behavior is critical for both homeowners and service professionals who need repeatable, measurable results instead of guesswork.

When to Use GLB Alkalinity Up 5 lb

GLB Alkalinity Up should be used whenever test results show total alkalinity below the recommended range, typically 80–120 ppm for most pools (system-dependent).

Common Use Scenarios

• New pool startups

• After heavy rain or water dilution

• Pools with chronic pH instability

• After acid washing or stain removal

• Seasonal openings and routine balancing

Correcting alkalinity early often reduces the need for repeated pH and chlorine adjustments later.

Improves Chlorine Efficiency & Swimmer Comfort

Chlorine sanitizes most effectively when water chemistry is stable. Low alkalinity causes pH drift, which weakens chlorine and increases consumption.

By restoring alkalinity, GLB Alkalinity Up helps:

• Improve chlorine performance

• Reduce sanitizer waste

• Maintain consistent free chlorine readings

• Lower long-term chemical costs

Stable alkalinity also contributes to more comfortable water, reducing irritation caused by corrosive or unstable conditions.

Safe for All Pool Types

GLB Alkalinity Up 5 lb is compatible with:

• Chlorine pools

• Saltwater pools

• Vinyl, plaster, fiberglass, and tile finishes

• Standard filtration and circulation systems

When used according to label directions, it will not damage pool surfaces or equipment.

Product Information

Buy with Confidence from Benchmark Pool Supply

When you purchase GLB Alkalinity Up 5 lb from Benchmark Pool Supply, you’re choosing a professional-grade balancing chemical trusted by pool technicians who know that proper alkalinity is the key to long-term water stability.

We recommend correcting alkalinity before adjusting pH or sanitizer levels because it simplifies maintenance, protects pool surfaces and equipment, and reduces unnecessary chemical use. This product is stocked because it delivers consistent, dependable results—exactly what effective pool care requires.