Activated charcoal is one of the most widely used substances to filter water. Used in both drinking water and for aquariums, activated charcoal--also known as activated carbon--is very porous. Because of this property, the filtering material traps impurities in the water and holds them, allowing clean, pure water to pass through. Many commercial water-filtering companies take advantage of this by filling their filters with activated carbon. Now you can make your own water filter at home using activated charcoal.
Clean and sterilise the glass pitcher using a solution of eight drops of bleach per gallon of water.
Place the coffee filter on the bottom of the pitcher, making sure that the filter covers the spout.
Purchase a 2-pound bag of activated charcoal from an aquarium-supply store. Soak the activated charcoal in water for 15 minutes to ensure that the carbon is saturated.
Fill the pitcher ¾ full of saturated carbon, leaving space at the top as a reservoir for water.
Fill the pitcher with water. Never fill the pitcher more than ½ full of water at a time. As water pours out of the spout at the bottom, it will trickle through the carbon and filter as it goes.
Save leftover carbon to change out every three to six months when the activated carbon in your filter is spent. To find a suitable glass crock-style pitcher, look for sun tea pitchers generally sold with picnic items during the summer.