Pumpkins, costumes, haunted houses, Halloween gives us all kinds of thrills. But the scariest thing you might face this year isn’t hiding behind a door. It’s flowing through your plumbing, sitting in your glass, running through your daily routine.

If you’re a coffee lover, you already know the drill: grind fresh beans, nail your brew method, and maybe even invest in that fancy gooseneck kettle everyone on Instagram seems to own. But here’s the plot twist: none of that matters if your water quality isn’t up to par.