Natural purified water is quite impossible nowadays because water supplies are contaminated of different natural and manmade pollutants. The most common pollutants are heavy metals like lead, microorganisms, volatile organic chemicals, chlorine, sediments and pharmaceuticals or pesticides. Using bottled water can be an option, but it is not the best choice because it is expensive and disposal of empty bottles can also be a problem.

Domestic water filtration can be healthy, cost-effective and environment friendly. The choice of water filter system can depend on the following factors: the quality of the tap water, the accessibility of the main water pipe, personal health problems and sensitivities, desire to have filtered water in the bathroom as well, kitchen space, piping system layout, and the number of faucets installed around the house.

A multi-stage domestic water filtration with active carbon can consist of a mechanical sub-micron particle strainer to get rid of the microorganisms and sediments, a granular activated carbon filter to suck in and remove volatile organic chemicals and other organic chemicals, a filter that will reduce chlorine content, and an ion-exchange filter to filter out heavy metals. Steps in multi-stage water filtration include removing turbidity and sentiments first then chlorine is reduced. After chlorine is removed, the heavy metals are gotten rid of next. The granular activated carbon filter then absorbs and removes organic chemicals. Finally, the sub micron filter filters the microorganisms and sediments.

Another type of domestic water filtration is reverse osmosis filtration. It is a technical process that requires pressure to be applied to the water to be able to pass through the semi-permeable membrane. Salty impurities like calcium, heavy metals, and magnesium are filtered out. After passing through the membrane, the water will then pass through the carbon filters to strain out the volatile organic chemical. With this type of filtration, vital minerals like calcium, potassium and magnesium are also removed. Also, with reverse osmosis, more water is wasted per gallon of purified water.

Water distillation is also a type of water filtration employed in the home. However, health care providers consider distilled water as unfit for drinking because it lacks minerals found in tap water.

Commercially available water filtration products are easy to install because they come with easy to follow installation manuals. Sometimes they also come with installation videos. They also include all the necessary parts in installing the chosen water filtration product. Prior to buying a water filter, the house owner can view the installation instructions online so he can decide if he can do the installation himself.

Turbidity and sediments, rather than being a health threat, are more of a nuisance because it spoils joy in drinking water. Chlorine, which is the cheapest alternative in killing microorganisms and bacteria in tap water, when combined with other pollutants can cause chloroform and other trihalomethanes generation which can cause cancer and other birth related defects. Lead which is a type of heavy metal can accumulate in the body and cause nervous defects. Microorganisms like cryptosporidium and giarda can cause stomach aches and diarrhea. Chemical contaminants found in unfiltered water can also cause cancer.