write a letter that you would give to a friend to get them to join too!). be sure to make it interesting, fun, and informative! it should be typed and be between half a page to a page in length! be sure to include your name! life around the house and allow them to make better use of their water supplies. as you continue to think about what water purifier to buy, ask these five questions. the answers will help you make the right decision what water purifier is the best one. 