Home water filtration systems come in several designs; ones that fit onto the plumbing under the sink, ones that can be fitted directly to a faucet, large whole home water filtration systems that filter the domestic water supply as it enters the home or even a pitcher system that filters water poured into a special pitcher.
Carbon Water Filters
Very fine particles of carbon are commonly used in home water filtration systems. A form of carbon known as activated carbon is highly effective at filtering sediments and removing chlorine by adsorption from domestic water supplies. The term ‘activated’ is used because the carbon particles all carry a minute electrical charge that will attract the negatively charged sediments and impurities.
Carbon water filters are highly effective and do not transmit any flavor or discoloring to the treated water. In a one pound weight of particulate carbon filter, there is the equivalent of one hundred acres worth of filtering capability. The actual size of the carbon particles determines the exact effectiveness of the filter.
Particle sizes range from 0.5 to 50 micrometers, whilst a smaller size is most effective, they will also need changing the most frequently. Carbon water filters are most commonly used as under-sink, on faucet and pitcher water filtering systems.
Reverse Osmosis Home Water Filtration Systems
If all of the water supply in use in your home needs filtering then a reverse osmosis home water filtering system is probably what you should be considering. Here the water is first passed through a pre-filter to remove any sediment. The water then passes through finer filter to remove things like heavy metals and finally through an ultra-fine filter, quite feasibly be a carbon one, capable of removing particles smaller than even bacteria.
Unlike a conventional filtering system, as the filters become contaminated reverse osmosis is used to keep the filters/screens clean using a technique commonly referred to as backwashing. Whilst reverse osmosis water filtration will deliver incredibly pure water the backwashing technique requires extra water to be used and it can take a gallon of water to complete the backwashing for every gallon of filtered water obtained.
Two things to consider here are how pure do you need your water to be, and wjether is water a scarce resource where you live? The level of water resource available to you is important in another way too, as without sufficient natural water pressure a booster pump will be needed for the reverse osmosis water filtration system.
Although well intentioned when it was first introduced, not everyone remains in favour of fluoride being put in our water supplies. Although fluoride in drinking water does help to reduce tooth decay, some 10% of the population are actually at risk from the fluoride in water as they are susceptible to dental fluorosis, which can appear as anything from white specks and streaks to a dark discolouring of the teeth.
Whilst a reverse osmosis home water filtering system will remove 90% of the fluoride from your water it cannot be guaranteed to remove it all. To ensure the total removal of fluoride you need to check that your water filtration system includes, or can be adapted to include, an activated alumina like aluminium oxide.
For anyone that has their own water supply such as a spring, well or bore-hole, the water filtration system of your choice can be fitted close to the source of the water supply or in any suitable outer building, to which the water can be routed to prior to it being used in the home.
Photo by tech109, Creative Commons Attribution