How does the brita filter work?!

Best Answer - Chosen by Voters

Brita filters have a double action:

1.The activated carbon filter eliminates bad odor and the taste of halogen compounds that chlorine makes when present in tap water.
2.The exchange ion resin lowers the concentration of calcium carbonates, accordingly softening tap water.

http://en.wikipedia.org/wiki/Brita

the water flows through activated carbon which removes impurties like metals and inorganic matter. it won't sterilize the water but it will make it better tasting. the activated carbon has little areas on it where those metals can stick to which is why the filters need replacing every 2 or 3 months.