Chlorine Removal Calculator

How It Works

Chlorine and chloramine in tap water are the number one cause of off-flavors in homebrew, producing medicinal or plastic-like phenolic tastes called chlorophenols. Free chlorine can be removed by boiling for 20 minutes or letting water sit uncovered overnight, but chloramine (used by most water utilities because it is more stable) cannot be removed by boiling. Campden tablets (potassium or sodium metabisulfite) instantly neutralize both chlorine and chloramine — one tablet treats 20 gallons. Alternatively, a carbon block filter removes both, but requires slow flow rates (under 0.5 GPM) to be effective against chloramine. Always treat your brewing water.