Water filters are attached either underneath the sink to filter the water before it comes out of the tap, or directly onto the faucet to filter the water as it leaves the tap. There are several different types of water filters, each of which uses a different substance to remove minerals and contaminants from your water. Because of this, each type of water filter carries with them a certain set of advantages and disadvantages. Understanding the differences between the two can help you choose the one that best fits your home's needs.
Carbon filters are the most common type of water filter on the market, namely due to their low cost. They come in a wide range of grades, with higher, more expensive grades filtering more elements out of the water, while inexpensive filters will only take out a few key minerals. They will filter out lead and mercury, as well as most types of bacteria from your water supply, but have trouble removing certain chemicals, such as fluoride or chlorine. Additionally, the filter will have to be replaced every few months or so depending on use to ensure that it continues working as intended.
Distillation filters work by heating the water up rapidly, causing it to turn into steam, and then condenses that steam back into water. In doing so, it will kill the bacteria in the water and remove some chemicals from the water. However, if there are chemicals that have a lower or similar boiling point to water, they will be vaporized and condensed as well. Additionally, distillation filters will not remove any minerals, like calcium or magnesium, from your water supply.
Reverse osmosis works by pushing water through a semi-permeable membrane that blocks out chemicals and bacteria. There is usually a secondary filter, normally carbon, which acts as a secondary line of defense for your water supply. Reverse osmosis filters tend to waste a great deal of water when compared to other types of filters, and are also significantly more expensive, though they are by far the most effective at eliminating contaminants in your water.
Water softeners are designed specifically to remove the minerals in your water supply that can clog your pipes and water fixtures. They work by binding sodium with the calcium and magnesium in the water, removing them from the supply. They are not able to remove chemicals from the water supply, nor are they able to kill bacteria. These are only ideal if you have hard water.
For more information on water treatments, talk to a professional.