How to Make Your Own Water Filter

When you make your own water filter, you can save the $30-$200 that you might expect to spend on a commercial unit. Here's how.

Materials For A Simple Water Filter
A water filter works by using fine materials to trap impurities as they flow through the device. Filter materials shouldn't introduce new impurities, which is why sand and gravel make good filtering agents. Here are the materials you'll need to make a simple water filter:

• 2-liter plastic bottle, cleaned and rinsed
• Coffee filter
• Rubber band
• 2 - 4 Cotton balls
• Activated charcoal, available at drug stores or pet shops (in the aquarium section)
• Fine sand
• Coarse sand
• Fine gravel
• Coarse gravel
• Bleach

Water Filter Construction Steps

• Cut the bottle. Carefully cut off the bottom third of the 2-liter bottle, keeping both pieces.
• Prepare the filter. Wrap the coffee filter over the neck of the bottle and hold it in place with the coffee filter. Place a few cotton balls in the neck of the bottle to act as a plug.
• Fill the filter. Add one cup of each of the filter materials in the following order: fine sand, activated charcoal, coarse sand, fine gravel and coarse gravel.
• Clean the filter. Slowly pour one to two gallons of clean tap water into the filter, allowing it to drain completely.
• Position the filter. Place the neck of the bottle into the bottom half of the bottle so that the filter sits upright.

Using Your Water Filter
Pour water slowly into the top of the filter, and it will collect in the bottom half of the bottle. Boil filtered water or add a teaspoon of bleach to each liter of water to remove any biological contamination.