Boil a pot of tap water. Let it cool. Now smell it again. If it smells like bleach on steroids, your city uses chlorine. That’s normal and safe. If it smells like rotten eggs after boiling, you have hydrogen sulfide gas. That’s not dangerous, but it’s definitely rude.
Pour that cooled water into a white mug. Look for orange or brown stains in the bottom. That’s iron sediment. Congratulations—you have liquid rust. Still safe, but your laundry will look like a tie-dye disaster.
Another quirky fact: Hard water boils faster because the dissolved minerals act like tiny seeds for bubble formation. So your calcium-rich tap water is a hyper-efficient pasta cooker.
