Reverse osmosis water filters are often used to purify bottled water, taking water right out of the tap and running it through a filtration system before selling it to you in those convenient and expensive bottles. You're not limited to purchasing water purified this way; instead, consider installing a filter to clean your water system. These filters run water through a membrane that allows only clean water to pass through; all other contaminants, from germs to chlorine, remain on the other side of the membrane and are flushed from the system. Almost every major contaminant is removed from your water with this method: chlorine and fluoride, arsenic, heavy metals, nitrates and pesticides, iron (you can get too much), sediments, bacteria and viruses, and even bad taste and smell.


Click here to see the top rated home water purifiers. Because of its effectiveness at removing contaminants, a reverse osmosis water filter is often called a hyperfiltration system. It works by sending water from your municipal or private supply through a series of small reservoirs in the filter unit, each containing the osmotic membrane. In the reservoir, clean water moves to the clean side of the filter, leaving contaminants behind. Water passes through via osmosis, not water pressure as is more common for other filters. That means that this filtration system is painfully slow. To address this problem, osmotic water systems include a tank where your clean water is deposited, providing a reservoir of drinking water in the amount of about fifteen gallons each day. This water is of bottled water quality, and if you buy bottled water every day, you can imagine how much money this can save you.

There are two types of membranes typical to reverse osmosis water filters. A thin film composite (TFC) membrane is very good at removing contaminants, but it is also very susceptible to damage from chlorinated water supplies. An activated carbon pre-filtration system may need to be installed upstream of your TFC membrane to remove chlorine before it gets to the membrane. The other type of membrane is the cellulose triacetate (CTA) filter, which is also good at removing contaminants though inferior to the TFC, but does not have a problem processing chlorine. Make sure before installing your water filtration system that you have the membrane most appropriate to your water system; a damaged membrane can force you to replace your entire filtration system.


Click here to see the top rated home water purifiers. For water that is contaminated with bacteria or other biological organisms, you may also need an ultraviolet filter. While an osmotic filter works quite well on biological organisms, it does not catch all of them; while one particle of mercury in your cleansed water will not kill you, a single bacterium in your clean water reservoir can multiply and eventually contaminate your entire osmotic water filtration system. To prevent this problem, add a UV water purifier to the downstream side of your filtration system. UV light is used to kill everything living in your water, which prevents your water from further contamination. This three-filter system - activated carbon, reverse osmosis, and UV purifier - will provide you and your family with the cleanest possible water supply.

The only drawback to the reverse osmosis water filtration system: it takes an enormous amount of water to produce those fifteen gallons a day, up to ten gallons of water for each clean gallon of water provided. Waste water from your reverse osmosis system should be redirected into a gray water reservoir if you live in a drought-prone area, where it can be used later to water your lawn.