Water Filter Information
There is a great deal of water filter information online. If you are curious about how they work or what chemicals are likely to be found in water, turn on your computer. Each manufacturer of water filters will list contaminants their filters remove. The best approach is to jot down what you like and dislike about each filter, and then compare your list when you're through looking at manufacturers' websites.
Sometimes the filter you need will depend on what's lurking in your water. It might be a good idea to have your water tested first before selecting a filter. Some filters are effective at removing chemicals while others are better at removing particulate contaminants. You may be able to save some money by customizing your filter.
Making Sense of Water Filter Information
Try not to be alarmed by the statistics you see on the Web. Often, water filter manufacturers will post statistics that reflect very poor water quality, when in reality, those statistics likely do not apply to you. That's another reason why it's good to have your water tested. There's no need to worry about contaminants that aren't in your water in the first place!
For those who get their water from private wells, water testing is especially important. That water is not being monitored municipally, and it's also not being treated prior to use. A whole house water purification system is highly recommended for those not on the municipal water system.