FAQs about Water Treatment

How does a water filter work?

Waterfilters are designed to reduce chemicals, biological contaminants, heavy metals, and other impurities from drinking water. Different filters filter water in different ways—by chemically attracting pollutants to the filter media, physically blocking contaminants from entering drinking water, or both.

How does reverse osmosis work?

Osmosis occurs when molecules pass through microscopic pores of a living or synthetic membrane. A difference in the concentration of molecules between one side of the membrane and the other causes the molecules on the more concentrated side to pass through the membrane to equalize the concentration on both sides.

As its name implies, reverse osmosis is when the opposite occurs. Instead of equalizing the concentration of substances on both sides of the membrane, water pressure pushes pure water to one side of a membrane, leaving a concentration of pollutants on the other. Reverse osmosis typically also employs two carbon filters, which together effectively remove organic contaminants, including chlorine and its byproducts, lead, mercury, and arsenic.

While reverse osmosis is one of the most effective means of filtration, it can also remove up to 95% of the beneficial mineral content in your water. Additionally, reverse osmosis generally requires between two to three gallons of water to produce one gallon of purified water.

How does a water softener differ from filtration products?

Although water softeners and waterfilters are included under the general term “water treatment,” they serve very different functions. Water softeners are designed to remove “hardening” minerals, including calcium and magnesium, from water that can damage pipes and appliances. Water softeners are not designed to remove dangerous contaminants from drinking water. Water filters, on the other hand, are designed to reduce unsafe pollutants in drinking water.

Do I really need a water filter?

According to The New York Times, the 35-year-old federal law regulating tap water is so out of date that millions of Americans can legally drink dangerously unhealthy tap water. Tap water has been found to contain dangerous chemicals such as radium, nitrate, arsenic, and chromium as well as pharmaceuticals. Even if municipal water treatment systems could completely purify water, transporting water from city centers to your home can leach lead and other contaminants into your water from pipes and fixtures. A good water filtration system in your home is the most effective and safest way to ensure healthy drinking water.

Is bottled water better than filtered water?

Researchers report that bottled water is not any purer that tap water—it just costs more. In fact, the U.S. FDA claims that bottled water companies who promote their brands as being safer than tap water are “defrauding” the American public. Unlike tap water, there are no federal filtration or disinfection requirements for bottled water. Furthermore, bottled water companies are not required to issue an annual “right to know” report that explains to consumers what is in bottled water. Additionally, over 60,000 plastic water bottles are disposed of daily in the U.S. alone.

On the other hand, most purification products provide superior water to both tap and bottled water, are more convenient to use, are environmentally safe, and cost a fraction of what bottled water costs.

What do you recommend for private well water?

The main difference between a well and a municipal system is that municipal water supplies are monitored and treated by the city and a private well is the responsibility of the well owner. Although the EPA does not monitor or regulate well water, the ground water that feeds wells can still become contaminated by landfill seepage, failed septic tanks, underground fuel tanks, fertilizers, pesticides, and runoff. To treat well water, it is important to accurately test the water. A comprehensive well water test kit can detect common and potentially hazardous contaminants in your well water and help determine what type of water filter you should purchase.

What is an activated carbon filter?

By itself, carbon is a highly absorbent material that can absorb thousands of different chemicals. Activated carbon is carbon with a slightly positive charge to it, which makes it even more absorbent to chemicals and contaminants. As your water passes over the charged carbon surface, the negative ions of the contaminants are attracted to the surface of the carbon granules.

Activated carbon effectively removes volatile organic compounds (VOCs), pesticides, herbicides, chlorine, benzene, radon, cancer-causing chlorine byproducts such as THMs, and hundreds of other chemicals in tap water. Carbon filters are not particularly effective at removing dissolved inorganic chemicals, minerals/salts, arsenic, and barium. Most home water purification systems include an activated carbon filter, either as a primary filter or as a pre-filter.

I've noticed small white particles in my filtered water. Should I be concerned?

The particles in your filtered water are most likely calcium or other mineral deposits and are completely harmless. Because carbon filters do not remove dissolved minerals from water, these particles may show up in your water as a result of build-up in the water lines leading to your refrigerator. If you are using ice cubes with your filtered water, the particles may be even more evident, as the dissolved minerals tend to separate from the water when frozen. If the mineral deposits become bothersome, you may wish to clean the plumbing leading to your filter with a cleaning solution designed to remove calcium, lime, and rust.

What is the difference between a nominal micron rating and an absolute micron rating?

A micron rating is a way of measuring a filter’s ability to remove contaminants based on the size of the contaminants. The two most common ratings are a nominal rating and an absolute rating.

A nominal micron rating indicates the average percentage of particles that a filter will retain. In other words, a nominally rated filter will typically filter anywhere between 50% and 95% of particles of a stated size, with 80% efficiency being the norm. For example, a 5-micron nominally rated filter will remove approximately 80% of contaminants 5 microns or larger.

An absolute micron rating indicates a more absolute percentage of particles a filter will retain. In other words, a filter with an absolute micron rating will remove close to 100% of particles of a stated size. For example, a 5 micron absolute rated filter will remove at least 98.7% of contaminants 5 microns or larger.

How do I get started?

Because there are many different types of filters, you may want to have your water tested to determine what kind of contaminants are in your water. Your local water center is also legally required to provide you with an annual confidence report that details what is in your water.

Our water experts are available to answer any questions you may have about water filtration or to help you determine what water system would most effectively meet your needs. Feel free to call us at (800) 565-7415 or chat with an expert online.

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