What is a Water Filter?

Let’s start with a few definitions of water filters.
From WordNet – a filter to remove impurities from the water supply
From Wikipedia – A filter is a device which removes impurities from water by means of physical barrier. Filters are used to treat water for irrigation, drinking water, aquariums, and swimming pools.
A Water Filter can be best described as a device used to remove something from water. You can use a hat, shirt, paper, carbon, string or pretty much anything else as a water filter. A hat or shirt are not exactly going to be the best filter, but it will filter out large items like fish, tadpoles, sticks, and maybe some dirt.
Most people think of water filters as the pitcher filter or faucet filter that they have in their house, but there are many other kinds of consumer water filters as well. Many homes have point of entry water filters which are also called whole house water filters and/or point of use filters also referred to as under sink water filters, shower filters, faucet filters, refrigerator and icemaker filters.
The question is, what do these water filters filter out of your water? The answer depends on two factors, what contaminants are in your water and what the filter you choose is rated for. To find out what contaminants are in your water, you will need to have your water tested using a drinking water test kit. Just because you have tap water does not mean that your water has safe levels of contaminants as contaminants can pass through city filter systems at times and some may even come from your own pipes! The EPA has standards for allowable level of contaminants in your water and in some cases these levels are not as low as you might think. Chlorine is used as a disinfectant in public water systems which is why most tap water smells and tastes like a swimming pool. Only you can decide what contaminants and at what levels you are comfortable with. Once you know what contaminants you would like removed from your water, you should choose a type of water filter specifically designed to reduce it from your water. For example, if Chlorine is a concern for you and your family, you will need a carbon based water filter. Recent studies have shown dangers to showering in highly chlorinated water as well as drinking it, so a point of entry, whole house, carbon based water filter system may be the best choice. If Arsenic is your main concern, then you will need to look at point of use reverse osmosis water filter systems.
Every impurity can be reduced by some means of water filtration but it is first important to understand what you are trying to reduce to pick the correct water filter system. Water filters come in many types such as pleated polyester, carbon wrapped paper, GAC (granulated activated carbon), Carbon Block, string wound, Polyspun and more. We will cover the difference, strengths and weaknesses of each type above in a future topic..