The $12 thermometer that proved my tap water was the problem
For two years I blamed my beans, my grinder, even my pour technique when my coffee came out bitter. Last Tuesday I bought a cheap instant read thermometer on a whim. Turns out my water was coming out of the tap at 185 degrees, not the 200 I assumed. I never checked because the kettle clicks when it boils. I adjusted my brew temp and the difference was night and day. Has anyone else found a dumb simple tool that exposed a basic mistake they'd been making for ages?
Honestly, I gotta push back on this. You said the kettle clicks when it boils, so you assumed the water was at boiling temp. But if your tap water is coming out at 185, that means your kettle is clicking way early, which sounds like a broken thermostat, not a water problem. The real mistake might be that you never questioned why your kettle clicks before it actually boils. That cheap thermometer just showed you what a $10 replacement kettle woulda fixed anyway. And bitter coffee can come from a million things, but blaming the water temp when your equipment is clearly off feels like a stretch.