Bottled water is not only expensive, but also bad for the environment (in terms of both packaging and import/export miles), while the water that comes straight from the tap can contain high levels of chlorine, lead, and other heavy metals and particles. Water filters are a great option for reducing potentially harmful elements and ensuring a fresh, clean taste. Your kettle will also thank you, as filtering water reduces limescale. But remember to replace cartridges regularly. Here’s what to look for.