Your home’s water is almost certainly contaminated. That’s because municipalities add chemicals to all water in their systems to kill germs and eliminate other toxins. But the same things that kill germs can make you sick as well. For this reason, it’s a good idea to investigate buying a home water purifier.

All water purification systems are different, but there are commonalities to three types of water purifiers: the ultraviolet purifier, the filtration system purifier, and the reverse osmosis water purifier. In some systems, all three of these filter types work together, but they can easily be installed as separate systems as well.

The simplest water filtration system is the activated carbon or ceramic water filter. Both of these systems use a granulated chemical – activated charcoal in the first case, diatomaceous earth (which is silicon-heavy) in the second case. There are also shower filters based on the same concept that use metallic filters because they function much better at high temperatures. In each case, water is forced through the filter by your water system’s normal pressure. As it passes through the water purifier, the chemicals inside the filter grab onto impurities in the water, but allow purified water to go on through the system. Sediments, germs, and certain chemicals are all left in the filter, which is changed for a new one periodically. These water purification systems are the cheapest home water purifiers.

An ultraviolet light purifier is also simple, but much more technologically advanced. This water purifier is not a filter at all, but a device that shines powerful UV rays down through your water, killing any microorganisms that may be there. While it won’t get rid of sediments and chemicals, an ultraviolet water purifier is among the best and most reliable removers of biological contaminants you can buy.

The reverse osmosis water purifier is the most technologically advanced. Originally invented to provide submarines with pure drinking water, a reverse osmosis water filter uses passive osmotic filtration to allow pure water to seep through a filter, leaving all chemicals on the other side. This water purifier is exceptionally effective, removing all sediments, most biological contaminants (a few slip through occasionally) and eliminating many chemical contaminants like chlorine as well. The only problem with a reverse osmosis water purifier is that it eliminates good minerals as well as bad, which is not healthy. Still, the water it provides is equal in purity to most bottled waters.

In more complex water filtration systems, multiple water purifiers are used to take advantage of their different strengths. The most common system is based around a reverse osmosis water purifier, but the water coming in is first forced through an activated carbon filter, then allowed into the reverse osmosis filter system. Finally, in the collection tank at the end the purified water is lit with an ultraviolet light, killing any biological contaminants that managed to get through. The results: the purest water you can get on this side of your wallet.

Trent Barrett is a consultant who reviews water filters at Home-Water-Purifiers.net. You can visit their homepage to learn more about Home Water Purifiers.