Expert Verified Updated: March 2026

Iron Stain Remover (Ascorbic Acid) Calculator

Calculate the amount of Ascorbic Acid (Vitamin C) needed to remove iron stains from pool surfaces.

Quick Conclusion
Use 1 lb of Ascorbic Acid (Vitamin C) per 10,000 gallons to lift iron stains from pool surfaces. Note that this will drop your chlorine to zero and require re-balancing.

Technical Comparison

Stain TypeAscorbic AcidCitric Acid
Metal (Iron)EliteModerate
OrganicFairFair
CalciumPoorGood

Actionable Steps

Pro-Tip

Ascorbic acid 'eats' chlorine. Ensure your FC is near zero before starting, and wait 48 hours before bringing chlorine back up slowly.

Frequently Asked Questions

Where to get it?

You can buy pure ascorbic acid from chemical suppliers or use specialized stain removers.

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