Under-Sink Water Purifier

An under-sink water purifier is a powerful, convenient way to improve the taste and safety of your tap water. They reduce a wide range of contaminants and are more comprehensive than pitcher, fridge or faucet-mounted filters.


These systems are easy to install and are tucked away out of sight under your sink. They are more efficient than countertop filter options and can handle higher volumes of filtered water.

Reverse Osmosis

Reverse Osmosis systems use a series of filters to remove dissolved contaminants from drinking water. The process uses the natural tendency of solutions with lower concentrations to migrate towards those with higher concentrations. The result is filtered water that’s far more pure than pitcher or faucet filters. They reduce a wide range of chemicals and minerals including arsenic, chromium, fluoride, radium nitrate, calcium, heavy metals, and disinfection byproducts from city or well water supplies.

All Reverse Osmosis systems start with pre-filtration to protect the membrane from sediment or chlorine that could clog the system. This is followed by a membrane that filters water at a molecular level, removing a large number of aesthetic and health-related contaminants. The resulting water is then stored in a tank until it’s needed. Most Reverse Osmosis systems have a final carbon stage that polishes the water for consumption.

Most Reverse Osmosis systems require a water pressure of 50-80 PSI to function correctly. They are also a significant investment and will require regular filter replacements and membrane replacement. Most RO systems will last for twenty years or more with proper care and maintenance.

Carbon Filtration

A carbon filter reduces impurities in your water by adsorption. Chemicals that give water objectionable tastes and odors, such as hydrogen sulfide (rotten egg smell), chlorine, and volatile organic compounds (VOCs) are stuck to the carbon. This helps prevent them from getting into your body. The granular activated carbon used in these filters has a large surface area and tiny pores, making it effective for this task.

Activated carbon works best for removing organic contaminants, but it can also remove heavy metals like lead, cadmium, and chromium; arsenic; and nitrates. This type of filter is also able to reduce pharmaceutical residue, which can enter drinking water from human waste, the improper disposal of medications, and agricultural runoff.

A simple under-sink water filtration system uses a carbon block to remove contaminants and improve the taste of your drinking water. The FRIZZLIFE Under-Sink Filter System filters up to two gallons of water per minute (GPM), which is ideal for home use. It is easy to install and features a built-in shut off valve, so you don’t have to turn off your water supply when changing the filter. It also comes with a nifty filter change indicator, which alerts you when it’s time to replace your filter. Unlike most other carbon filters, the FRIZZLIFE model doesn’t require a separate sediment filter.

Micron Filtration

When choosing a filter it is important to consider the micron rating. A micron is one millionth of a meter. Typically, the smaller the micron size, the finer and more precise the filtration.

A micron rating of 0.5-micron or lower is best for whole house water filters because it can help remove harmful bacteria and other small particles from your tap water. These tiny particles can irritate your skin, eyes and lungs and can also be absorbed into your body through inhalation.

In addition to bacterial removal, this type of filter can reduce other impurities such as chlorine, organic chemicals and lead. These are often found in the water supply due to industrial runoff or leaching from old plumbing systems in certain parts of the country.

If you’re looking for a system that offers first-of-its-kind effectiveness to clear 88 contaminants including arsenic, fluoride, lead and PFOA/PFOS, check out the Brondell H20+ Circle Reverse Osmosis Water Filtration System. This Gold-Seal certified undersink water filter has four stages of filtration, a 6-liter storage tank and an automatic faucet.

Another option for a whole home water filter is the 50-micron model. It is a great mid-range option that offers the advantages of a finer filter without the clogging issues. It can still remove large sediment particles from well and city water as well as rust flakes. This type of filter can also reduce toxins such as heavy metals, chlorine and organic chemicals.

Ultraviolet Filtration

UV water purification disinfects your water using ultraviolet rays to kill bacteria, viruses, mold, and other pathogens in your water. It is especially effective against waterborne cysts such as Giardia and Cryptosporidium, and it can also help kill chlorine-resistant microorganisms like E. coli. It is a safe, natural, and chemical-free way to clean your drinking water. It works best when paired with other filtering methods that physically remove contaminants from your water such as carbon or reverse osmosis filters.

Unlike other filtration methods that may add chemicals to your water, UV does not alter the taste, color, or smell of your water. It requires clear water to work, so pre-filtration is recommended to ensure the light can reach all of the microorganisms in the water. UV treatment can also de-chlorinate and de-ozonate your water, making it an excellent addition to any multi-stage water treatment process.

UV systems are easy to install and require little maintenance, but they do need a reliable source of electricity and must be placed in an area where the light will not be blocked. You will need to replace the UV lamp every year or so, and you will also need to replace the sleeve occasionally as it gets dirty. Choose a system that is properly sized for your household peak demand flow rate to ensure maximum effectiveness.