When I noticed green fuzzy things floating around the gallon water filter we kept in the fridge, I knew it was time for an upgrade. And though New York City is said to have grade-A tap water (it’s ...

Katya Mosely remembers the exact moment it all began, a few years ago. “It was my daughter’s piano teacher,” she says. “She had a 6-inch-long stick of charcoal floating in her glass water bottle. I ...