Think about the last time you made a pot of coffee. You probably used tap water straight from the faucet, and it tasted just fine, right? Tap water is a mineral cocktail—it comes complete with calcium, magnesium, and tiny amounts of fluorine added to keep your teeth strong.
But here’s the kicker: that same water that makes a great cup of joe can also leave white, crusty spots on your glassware. Those little flakes are hard water deposits, and they’re proof that tap water is carrying a lot of extra stuff around.
My grandmother used to say, “If it leaves a ring in the bathtub, it’s working hard.” She wasn’t wrong. Tap water is a hard worker, but sometimes it overstays its welcome in your coffee maker or on your shower doors.
