Expert Verified Updated: March 2026

Dry Acid (pH Down) Calculator

Looking for a safer alternative to liquid acid? Use this calculator for Sodium Bisulfate (Dry Acid) to lower your pool's pH and Alkalinity safely.

Quick Conclusion
Dry Acid (Sodium Bisulfate) is a safer, granular alternative to Muriatic Acid. To lower pH from 8.0 to 7.5 in a 10,000-gallon pool, you need approximately 1.5-2 lbs. It also lowers Total Alkalinity.

Technical Comparison

Acid TypeSafetyCost Efficiency
Muriatic (Liquid)LowerElite
Dry AcidEliteModerate
Sulfuric AcidDangerHigh

Actionable Steps

Pro-Tip

Vinyl Pools: Dry acid is highly recommended for vinyl liner pools because it won't bleach or damage the liner as quickly as a splash of liquid muriatic acid can.

Frequently Asked Questions

Does it expire?

Keep it dry and it will last for years.

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