Add Yahoo as a preferred source to see more of our stories on Google. The Brita Elite filter (i.e., blue ones, $35) can be used for up to six months (about every 120 gallons). When Should I Change My ...

Plus, how to recycle those old filters. Many of us trust that our Brita water filters are removing contaminants from our tap water—but if you haven't replaced the filter in several months (er, years), ...