Your Guide to Carbon Filtration Solutions

At Moen, your family’s water quality and experiences with water are important to us. That’s why we’re giving you tools and resources to help you better understand and improve the quality of drinking water in your home. There are lots of strategies and solutions that you can use to filter your water, and chances are, you may already have a filter you use in your home, like a pitcher or water dispensing refrigerator. But no matter what filtration option you choose, the search for the right solution should start by learning about your local water quality, the many different types of filtration technology and identifying what your family’s needs are when it comes to water quality.

Water Treatment System Standards

Even though water treatment products are regularly found in homes now, there are no federal regulations for these household water treatment products. However, the National Sanitation Foundation (NSF) developed voluntary standards through an independent product testing, inspection and certification process. As an organization accredited by the American National Standards Institute (ANSI), the NSF developed protocols that establish minimum requirements for the safety and performance of products designed to treat drinking water.¹

Some NSF/ANSI standards are specific to a particular treatment technology. For example, NSF/ANSI 42 & 53 are specific to adsorption filters, like activated carbon filters. There are also standards that are specific to a particular class of contaminants, like emerging contaminants.² Residential water treatment systems can also be certified to multiple standards depending on the types of filters they use and the contaminants they’re certified to remove.

Whenever you’re shopping for a new water treatment product or system for your home, be sure to check that it’s certified by the NSF and look for the NSF mark on product packaging. Just because a filter, purifier or treatment system is certified to a particular NSF/ANSI standard, it doesn’t mean it’s been certified to remove all the contaminants under that particular standard. Therefore, it’s best to review the contaminant claims list for a particular residential water treatment system to see which contaminants the filter is certified to remove.

To learn more about specific treatment products, you can use this Water Quality Association tool.

What are Carbon Filters?

Carbon filters remove contaminants in drinking water through a process called adsorption, where particles stick to the surface of a piece of treated carbon (as opposed to absorption where particles soak through).³ Carbon filters are made up of activated carbon, a material that is manufactured by treating carbonaceous materials, like coal, nutshells, peat and wood, at a high temperature without the presence of oxygen.⁴ The activation process creates a porous material with many tiny pockets, giving the substance an extremely high surface area to volume ratio.⁵ Activated carbon’s high surface area is an important feature since contaminants adhere to the carbon as the water passes through the filter.

A wide range of contaminants, particularly organic contaminants, can be removed using activated carbon, including compounds that contribute to taste and odor concerns, like chlorine, and other volatile organic compounds.⁶ When purchasing a carbon filter, it’s best to check the manufacturer claims to confirm the compounds and contaminants the filter is removing. There is a wide variety of carbon filters available, from filter pitchers and faucet attachments to single-stage and multistage filters, so it’s important to explore the pros and cons of each type before buying a new filtration system for your home.

Refrigerators

Most water dispensing refrigerators have an integrated carbon filter to treat your water and improve the taste. These filters need to be replaced every 3 to 6 months, so it’s important that you replace them throughout the year to ensure your refrigerator is treating your water effectively and not degrading the quality.

Pros	Cons
Easy to use	Limited options based on refrigerator brand compatibility
Easy to maintain and replace	Slow water flow
Convenient	Often need to replace with name-brand filter that can be more expensive

Pitchers with Filters

A filter pitcher is a convenient and cost-effective way to filter your family’s water, reduce odor and filter out chlorine and other contaminants. However, it’s important to replace your filter often — every 2 to 3 months — to ensure the best performance, and if you have hard water, you may need to replace it more often.

Pros	Cons
Easy to use	Short filter life
Low cost	Slow filtration
Many styles, shapes and sizes available	Limited capacity
	Pouring challenges

Faucet Attachments

Another easy way to incorporate filtration into your kitchen is to add a carbon filter faucet attachment to your faucet in place of an aerator. These adapters are DIY and budget friendly, and only need to be replaced every 3 to 4 months.

Pros	Cons
Easy to install	Slow pouring
Low cost	Leaks shortly after install
Instant filtered water at any time	Adapters don’t always fit existing faucet
Easy to switch between filtered and unfiltered water	Water may not taste much different after installation

Countertop Single-Stage Filters

A single-stage countertop carbon system filters your water once before dispensing it through your faucet. These systems help improve the taste of your water while commonly filtering out chlorine, chloramines, lead and mercury, and your filter only needs to be replaced every 12 months.

Pros	Cons
Easy access for filter replacement	Short lifecycle
NSF certifications	Filters single water source
	Doesn’t dispense chilled or warm water

Under Counter Filters

Under counter filters are mounted in the cabinet beneath your kitchen sink to provide you with filtered water directly from your tap. Single-stage systems filter your water once before dispensing it through your faucet, whereas multi-stage filters provide a more thorough filtration to improve taste and odor and to remove additional contaminants. Single-stage filters only need to be replaced every 6 to 8 months, but multi-stage filters should be replaced every 6 months.

Single-Stage Filters

Pros	Cons
Easily installed on existing faucets	Can leak and cause water damage
Doesn't take up counter space	Low volume and pressure
The most compact under-counter filtration system
Entry level price points

Multi-Stage Filters

Pros	Cons
Hidden out of sight	Short lifecycle
Improves taste of water	Filters single water source
Fits most under-counter configurations

Whole Home Carbon Filters

Whole home carbon filters are point-of-entry treatment systems that are installed on your main water line. These ensure that every point of use in your home has filtered water, from your showers to your kitchen tap. As water enters your home, it’s continuously treated to give you high water quality at every point-of-use throughout your house.

Pros	Cons
Conveniently treats all water in your home	High price point
Low maintenance	Can’t filter contaminants from pipes or fixtures, like lead and copper
Can treat thousands of gallons of water per day
Can prevent scale buildup from hard water

What are Particle Filters?

Particle or sediment filters are designed to remove suspended particles that may end up in drinking water, such as sand, clay, silt and organic matter. A particle filter removes these particulates by using a size separation barrier where the average pore size of the cartridge determines what size particles are filtered out.

Typical household units have ratings between 0.5 and 50 microns, where the rating indicates the smallest size particle the particular filter is designed to remove.⁷ Removing particulates and sediment can also prevent clogs and damage to your showerheads and faucets, while protecting any other filtration systems you may have downstream in your home, like reverse osmosis or activated carbon filters.

Proper Filter Maintenance

In order for filters to treat water effectively, it’s important to maintain them properly, since an improperly maintained filter may actually degrade the tap water quality it’s designed to improve. For common household filters, such as particle filters and carbon filters, maintenance often boils down to replacing the filters on a recommended schedule. When filters aren’t replaced in a timely manner, their effectiveness and performance can deteriorate.

Carbon filters can harbor microbial growth and biofilms on the filter surface, causing the bacterial count of water exiting the filters to be higher than the original tap water.⁸ Researchers are still studying the degree to which bacterial and biofilm growth on filters are considered health hazards. But they recommend regularly changing filter cartridges and flushing water through the filter in the morning before drinking or using it. Be sure to follow the manufacturer’s recommendations for filter replacement, to avoid unintentionally causing tap water degradation, low flow rates through the filter, damage to the filters or other negative impacts.

What Water Filtration Option is Right for Me?

As you’re searching for the right water filtration option for your family, you should take a few factors into consideration, including:

How many people are in your household, and if you have children and pets
If you own or rent your home and when it was built
If you have a private well
The amount of space beneath your kitchen sink

It’s also important to consider specific goals you may have for improving your water quality, like:

Improving taste
Reducing odor, water discoloration, hardness and build up
Reducing negative impact on hair and skin
Improving water for your plants and garden
Reducing environmental impact

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