You may have seen the term “KDF” filtration when shopping for a new shower filter. But what is KDF?
In a nutshell, KDF is a type of media used in many water filtration systems. KDF stands for “Kinetic Degradation Fluxion.” It’s a high-purity, granulated copper-zinc alloy that removes chlorine, lead, and other heavy metals from water. KDF also inhibits the growth of bacteria and algae.
Simply put, when found in a shower filter, it can remove all the yucky stuff from your water that can cause skin irritation, dryness, brittle hair, and a whole host of other problems.
Types of KDF Filters
KDF filters are available in several varieties:
- KDF-55: When water passes through this filter type, a redox reaction changes harmful contaminants into harmless ones. KDF-55 effectively removes chlorine and heavy metals from your water, making it one of the most common filtration media used in shower filters.
- KDF-85: This is a different media that targets various contaminants. KDF-85 is primarily used to remove iron, hydrogen sulfide, bacteria, algae, fungi, and scale.
- KDF-F (Fines): This KDF filter is used in tandem with an activated carbon filtration media to remove chlorine and bacteria.
- KDF-C (Coarse Mesh): This removes and/or reduces heavy metals and chlorine.
Who Makes KDF Shower Filters
While KDF filters may seem like a generic filtration system, they are a patented technology made by Michigan-based KDF Fluid Treatment, Inc.
Effectiveness of KDF Filtration Media
KDF remains a popular medium for many shower filters as they can remove up to 95% chlorine from water. Unlike most filters that lose their filtration quality with each passing gallon of water, KDF continues to work long after the initial installation.
As you can see, the white line in the graph is a KDF 55 filter with over 90% chlorine reduction after 30,000 gallons of water. In comparison, the fast-sloping green and red lines are GAC (granulated activated carbon) filters that begin to lose effectiveness after filtering 8,000 gallons of water.
Are KDF Filters Independently Tested?
KDF media is tested and certified by NSF International. It adheres to standards 42 and 61.
NSF standard 42 certifies the following:
Filters are certified to reduce aesthetic impurities such as chlorine and taste/odor. These can be point-of-use (under the sink, water pitcher, etc.) or point-of-entry (whole house) treatment systems.https://www.nsf.org/consumer-resources/articles/standards-water-treatment-systems
Whereas NSF standard 61 certifies the following:
Minimum health-effects requirements for the chemical contaminants and impurities that are indirectly imparted to drinking water from products, components and materials used in drinking water systems. This standard does not establish performance, taste and odor, or microbial growth support requirements for drinking water system products, components or materials.https://www.nsf.org/knowledge-library/nsf-ansi-standard-61-drinking-water-system-components-health-effects
Per NSF, they verify the reduction performance of KDF filters against the claims made by the manufacturer. We found the KDF Fluid Treatment, Inc certifications on the NSF website. Here is their certificate for NSF/ANSI 42 and NSF/ANSI/CAN 61, should you want to learn more.
Will a KDF Filter Soften Hard Water?
No point-of-use filtration media will effectively soften hard water. Instead, a whole-house water softener is necessary to remove the excess minerals (calcium and magnesium) in hard water. However, KDF can reduce the formation of scale on external surfaces, which is often caused by hard water.
How Long do KDF Filters Last?
Per KDF Fluid Treatment, Inc, their KDF media will last “more than 6 years” (source). But, of course, it usually isn’t a good idea to wait this long, as many other stages within your shower filter will degrade well before the KDF media does. So you’ll still want to follow the company-recommended maintenance schedule.
Shower Filters with KDF Media
There is no denying that KDF is an effective filtration media. If you’re looking for a shower filter with KDF, consider the following:
- AquaSana AQ-4100: This popular model by AquaSana contains a combination of KDF and coconut shell carbon. It is a bit pricey, but it performs exceptionally well.
- Jolie Filtered Shower Head: This elegant and sleek shower head contains a KDF-55 media and calcium sulfite. It is one of the more expensive shower heads on the market, but it will last up to 3 months before replacement is necessary.
- SparkPod Shower Filter: KDF, along with 14 other stages of filtration media, are found within this ultra-powerful shower filter. Similar in design to the AquaBliss SF100, it is compatible with most shower head types.
KDF is a highly effective filtration media you should consider when purchasing your next shower filter. KDF is one of the few media that carries an independent NSF certification and has lab tests that back the performance.