Water for Espresso & Coffee: TDS, GH/KH, and the Best Bottled and Filtered Options
About 98% of the coffee in your cup is water. Get the water wrong and the best beans, the best grinder, and the most precise pour over technique can’t save it — coffee will taste flat, sour, bitter, chalky, or all four at once. Get the water right and a 200-gram bag of medium-priced single origin starts to taste like the $40 cuppings at the roaster. This guide covers the full water-for-coffee picture: the TDS, GH, and KH numbers that matter, the Specialty Coffee Association’s Gold Cup standard, how to read a bottled-water label, the bottled waters and filters that actually work for espresso, Third Wave Water and Lotus Coffee Drops for remineralizing distilled or RO water, what a DIY remineralization recipe looks like, and the maintenance schedule that keeps your espresso machine alive in a hard-water area. ...