The following is a listing and description of Point of Use Water Filtration Devices (as opposed to whole house) and their particular strengths and drawbacks of each.
ACTIVATED CARBON / ADSORPTION - Activated carbon surface attracts and holds tiny particles that can cause poor odor and taste. Enhanced systems can also reduce trihalomethanes and lead. These systems will produce decent tasting water at an affordable price , but is incapable of removing the broader spectrum of contaminants.
FILTRATION - Filters, like sediment filters for example, will help remove turbidity and particulate matter that affect the overall appearence of water. Filters alone will do very little to remove tastes and odor producing contaminents as well as some types of chemical contaminants.
ACTIVATED CARBON AND FILTRATION - This combination is an effective means for reducing the contaminants detailed in each listed above.
DISTILLATION - Distillation, in general terms, is a process by which a substance is heated, vaporized and then condensed to rid the substance, in this case water, of most chemicals, bacteria and viruses. This process is costly and the equipment has to be maintained for proper function. The cleaning of the unit to remove sediment and scale requires the use of highly corrosive acids. This is not normally recommended for residential use.
REVERSE OSMOSIS - These systems utilize the existing water pressure in your home piping system to force water molecules through a semi-permeable membrane, causing contaminants to be left behind. This process uses no chemicals or electricity and is very effective in filtering out heavy metals, nitrates and pesticides. The downside to this technique is that to make one gallon of filtered water, four gallons must be filtered and sent down the drain. If the use of reverse osmosis filtered water is specifically for cooking and drinking as designed, the expense you will see is minimal. Additionally, water in nature is recycled and it's really not wasted in the overall scheme of things.
REVERSE OSMOSIS FROM ULTRAVIOLET - This device will allow you to have all the benefits of the regular reverse osmosis system as well as the added effects of ultraviolet light. UV lights kill bacteria and viruses with no harmful by-products or undesirable odors.
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