Why Water Matters More Than Most People Think

Tea is somewhere between 98 and 99% water. That number alone should settle the argument: water isn't a neutral vehicle for delivering leaf flavor, it's most of what's actually in the cup. Brew the same leaf with two different waters and you'll taste two different teas, even with identical leaf, temperature, and time.

Mineral content is the biggest variable. Water that's too soft (very low mineral content, like some distilled or heavily filtered water) tends to pull flavor out flat and thin — there's nothing for the tea's compounds to bind to on the way to your palate. Water that's too hard (high in calcium and magnesium) does the opposite: it mutes aromatics and can leave a chalky, dull film, especially noticeable in lighter teas like green or white where there's less going on to cover it up. Most tap water sits somewhere in between, which is fine for everyday drinking — the real damage tends to come from chlorine and other treatment additives, which taste like exactly what they are.

If you're brewing something you actually care about — an aged sheng, a good Tie Guan Yin — filtered water (a basic carbon filter is enough) or a light, low-mineral bottled water removes most of the worst offenders without stripping the water bare. Some serious tasters go further and use specific mineral-water brands known to work well with tea, the way a coffee shop dials in water hardness for espresso, but that's a rabbit hole you can ignore until you've already fallen in love with the basics.

The one thing water quality can't fix is bad temperature or timing — no filter saves an oversteeped green tea. But once you've got those right, better water is the cheapest, easiest upgrade to a cup you'll notice immediately and won't want to go back from.