To be safe, check you State's drinking water rules. Although the Safe Drinking Water Act assures us of safe drinking water from the tap, many people buy systems to treat their water further. In other areas, post tap water treatment is done to remove the contaminants contributing to secondary drinking water standards. Such treatment often improves the appearance and flavor of water. Carbon Filters Work by passing water over activated carbon granules, and absorb the contaminants onto the activated carbon surface.
Carbon filters are most effective for organic molecules and ineffective for dissolved ions.
Carbon filters are best at removing bad taste, odor, chlorine, and pesticides. They many help with sediment and turbidity, but do not help with microbial contamination, lead and other heavy metals, sodium, waste, fluoride or hardness. Reverse Osmosis Reverse osmosis units work by forcing water through a semi permeable membrane. Clean water passes through the membrane and the contaminants remain behind to be flushed down the drain. Reverse osmosis systems are very low volume and usually limited to cleaning of drinking water, and the membrane needs to be replaced annually.