Does water quality really matter for tea?

Water is 98% of your cup, so yes — it matters enormously. Target soft to medium-soft mineral content (TDS 30–80 ppm). Heavy chlorination dulls aromatics; very hard water (lots of calcium) makes tea taste flat and forms a scummy film on top. Filtered tap is the easy upgrade. Bottled spring water like Volvic or any low-mineral spring works well for delicate greens and whites. Avoid distilled — it makes tea taste hollow.