Turbid water (or discolored water) is an observable characteristic of water and is measured by the amount of light that is scattered by material in the water when a light is shined through it. The higher the intensity of scattered light, the higher the turbidity. Material that causes water to be turbid include clay, silt, very tiny inorganic and organic matter, algae, dissolved colored organic compounds, plankton and other microscopic organisms. Higher levels of turbidity can sometimes be caused by water main breaks in public water supplies.
Excessive turbidity, discolor or cloudiness in drinking water is aesthetically unappealing, and may potentially represent a health concern. Turbidity can provide food and shelter for pathogens. If not removed, the causes of high turbidity can promote regrowth of pathogens in the water, leading to waterborne disease outbreaks. Although turbidity is not a direct indicator of health risk, numerous studies show a strong relationship between removal of turbidity and removal of protozoa. The particles of turbidity provide “shelter” for microbes by reducing their exposure to attack by disinfectants. Microbial attachment to particulate material has been considered to aid in microbe survival. Fortunately, traditional water treatment processes have the ability to effectively remove turbidity when operated properly. (Source: U.S. Environmental Protection Agency)
There are various types and sizes of water filter cartridges with differentiating features relating to what you are trying to mechanically remove from the water. These filters do not work on removing dissolved impurities from the water as other technologies must be used for this purpose.
SEDIMENT WATER FILTER CARTRIDGES, as their name implies, are for removing sediment (particulate matter) from the water supply. The key characteristics relate to the micron rating of the filter designed to remove particles at or greater than a specified size and also capacity in terms of how long the sediment filter will work before it is no longer able to remove sediment. Specifying a micron rating that is too small for installation at the water’s point of entry into your home, for example, may cause an unacceptable drop in water pressure. Specifying a micron rating that is not small enough may produce less than optimal results in keeping sediment out of your water supply.
Sediment filters are important because sediment can be abrasive to all of your water using appliances and can also negatively affect other types of water filtration or water softening equipment that you may have installed or are planning to install in your home or other facility. Removing sediment is also a good step in providing better drinking water, although not the only step if a higher level of purity is desired. For more on high quality drinking water, see the link at http://reverse-osmosis/
CARBON WATER FILTER CARTRIDGES use activated carbon to remove chemicals (such as chlorine, volatile organics and others) and some bad tastes and odors from water. Carbon filters are also components of reverse osmosis purification systems to remove chlorine from water prior to flowing to the systems’ membrane which can be negatively affected by the chlorine. Water passes through activated carbon, which is porous, trapping certain particles that are attracted to the porous material in a process known as adsorption. At some point, adsorption capacity is exceeded and the filter must be changed in order to be effective. As with sediment water filters, the micron rating and size of the filter must be matched to the specific situation.
In situations where there is high water usage and frequent cartridge filter change-outs doesn’t make sense, a point of entry filter vessel (as seen above) may be the solution. These systems do not require the frequency of change-outs that cartridge filters do and have the ability to automatically clean themselves, extending the life of the media inside the tank. Another example would be if your town supplied water is high in chlorine and you wish to eliminate it from your water supply. A point of entry carbon water filter will have enough capacity to last much longer and also remove more of the chlorine due to longer “contact time” that the water has with the filter.