Tea 101
Water for Tea
How water quality affects tea flavor. Mineral content, pH, filtration, and why brewed tea that is 98% water deserves great water to start with.
Introduction
Brewed tea is over 98% water, yet most tea drinkers pay far more attention to the leaf than to the water. {{glossary:water-quality}} is arguably the most impactful and underappreciated variable in tea brewing. The ancient Chinese tea sage Lu Yu, writing in the 8th century, devoted an entire chapter of the Cha Jing to water selection.
How Minerals Affect Extraction
Soft water (low mineral content, under 100 ppm TDS) extracts tea compounds more efficiently, producing brighter, more aromatic cups with better color clarity. Hard water (high calcium and magnesium, over 200 ppm TDS) buffers acidity and binds with {{glossary:polyphenols}}, creating a flatter, duller brew. Hard water often leaves a chalky film on the surface of cooled tea — a clear sign that mineral interference is suppressing flavor.
The Ideal Range
For most teas, the optimal water contains 50-150 ppm total dissolved solids with a pH between 6.5 and 7.5. This provides enough minerals to carry flavor while avoiding the suppressive effects of hard water. Spring water from volcanic or granite formations often naturally falls in this range.
What to Avoid
Tap water with chlorine or chloramine introduces off-flavors. Carbon filtration or a simple Brita-style pitcher removes chlorine effectively. Distilled or reverse-osmosis water lacks the trace minerals that support flavor extraction, producing a flat, lifeless cup. Re-boiled water loses dissolved oxygen, which some tasters believe reduces vibrancy, though this effect is subtle.
Practical Recommendations
For most people, filtered tap water through a carbon pitcher or under-sink filter produces excellent results. If your tap water is very hard (above 200 ppm), consider a custom mineral blend: start with distilled water and add mineral concentrates designed for coffee and tea brewing. The difference between bad water and good water is often more dramatic than the difference between a $5 and $50 tea.
Temperature Control
{{glossary:water-temperature}} is equally critical. An adjustable-temperature kettle is the single most useful tea accessory. Boiling water for delicate green tea is the most common brewing mistake worldwide.