Solved my sour taste problem with a $4 thermometer and a 30 second wait
Honestly I was about to give up on my pour over because every cup came out sour no matter what I did. I was grinding finer, going slower, nothing helped. Then last Tuesday I stuck a cheap instant read thermometer in the kettle and saw my water was sitting at 187F, way below what I thought. I started waiting 45 seconds after the boil and now the water hits around 200F, and the sour thing just went away. Has anyone else found their kettle runs cooler than they assumed?
187F is basically cold brewing temps, so yeah that's gonna give you sour cups every time. But a $4 thermometer "solving" it forever seems a little too clean, kettles drift and tap water temps change with the seasons. You probably just fixed one bad variable and got lucky, check it again in a month before you call it solved.