There are two other ways to make potable water. The first is to treat contaminated water with a chemical. Iodine based tablets are manufactured for this purpose. Keep in mind that these tablets do not store indefinitely. New tablets should store approximately three years.
Some estimates are shorter if the bottle has been opened.
Water purified with chemicals may still look ugly and smell bad,straining through a cloth is recommended, especially if the water is cloudy. You may need a waiting period to ensure potable water. The PentaPure system, with Products such as the Water Jug and Oasis,use a chemically treated resin bead that water passes through. Water is then safe to drink. The second way to treat contaminated water is with water filters.