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This review article discusses the different types of reverse osmosis water filters used for common contaminants in your water.
Our primary goal is to answer one question: does the filter do what it says it will do?
To answer this question, we look for three specific criteria:
1. Number of contaminants the filter claims to remove
2. Quantity and quality of 3rd party certifications verifying contaminant reduction claims
3. Supporting testing data that verifies contaminant reduction rates
These three criteria are essential in determining if you are purchasing a high-quality filter.
Filters we recommend have the highest level of certifications to back up their claims and are either directly certified by NSF or they are certified to NSF standards by a reputable 3rd party organization such as the Water Quality Association (WQA) or the International Association of Plumbing and Mechanical Officials (IAPMO)
The Aquasana SmartFlow is NSF Certified to remove/reduce 90 total contaminants. The filter includes 4 stages – activated carbon, reverse osmosis, activated carbon, and a remineralizer for maximum removal efficiency. The remineralizer section helps increase the acidic pH commonly produced by RO water and increases the mineral and alkalinity levels.
This filter is certified by WQA to NSF standards to remove or reduce the following contaminants. For more details on removal rates see the Performance Data Sheet.
Chlorine, Mercury, Lead, MTBE, Arsenic Pentavalent, Barium, Cadmium, Chromium, Copper, Fluoride, Nitrate/Nitrite, Radium, Selenium, TDS, Turbidity, Atenolol, Bisphenol, Carbamazepine, DEET, Estrone, Ibuprofen, Linuron, Meprobamate, Metolachlor, Naproxen, Nonyl phenol, Phenytoin, TCEP, TCPP, Trimethoprim, Perfluorooctanoic acid (PFOA), Perfluorooctane sulfonate (PFOS), Organic chemicals, VOCs, alachlor, atrazine, benzene, carbofuran, carbon tetrachloride, chlorobenzene, chloropicrin, 2,4-D, dibromochloropropane (DBCP), o-dichlorobenzene, p-dichlorobenzene, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,2-dichloropropane, cis-1,3-dichloropropylene, dinoseb, endrin, ethylbenzene, ethylene dibromide (EDB), haloacetonitriles (HAN), Bromochloroacetontrile, Dibromoacetontrile, Dichloroacetontrile, Trichloroacetontrile, haloketones (HK), 1,1-dichloro-2-propanone, 1,1,1-trichloro-2-propanone, heptachlor (H-34, Heptox), heptachlor epoxide, hexachlorobutadiene, hexachlorocyclopentadiene, lindane, methoxychlor, pentachlorophenol, simazine, styrene, 1,1,2,2-tetrachloroethane, tetrachloroethylene, toluene, 2,4,5-TP (silvex), tribromoacetic acid, 1,2,4-trichlorobenzene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, Trihalomethanes (THMs), Bromodichloromethane, Bromoform, Chloroform, Chlorodibromomethane, Xylenes
This filter was tested and certified by WQA to NSF/ANSI Standards 42, 53, P473, 58 and 401 for the claims specified on the Performance Data Sheet.
NSF/ANSI 42 – Reduction of aesthetic contaminant concerns such as chlorine, taste and odor, and chloramine.
NSF/ANSI 53 – Over 50 health-related contaminant reduction claims.
NSF/ANSI 401 – Removal of 15 specific contaminants related to prescription drugs, over-the-counter medications, herbicides, pesticides and chemical compounds.
NSF/ANSI P473 – Remove per- and polyfluoroalkyl substances (PFAS) from drinking water.
NSF/ANSI 58 – Reverse osmosis (RO) water treatment systems that remove a wide range of contaminants
The Carbon Filters will last for 365 gallons or up to 6 months. The RO membranes and remineralizer will each last for 12 months.
More 3rd party certifications than any other counter top or tankless unit by far. This filter is certified by IAPMO against NSF standards 42, 53, 58. 401, and P473. Very low waste flow at only 25%.
This filter is certified by IAPMO to remove or reduce the following contaminants. For more details on removal rates, see the Performance Data Sheet.
Mercury, Lead, Arsenic, Barium, Cadmium, Chromium, Copper, Fluoride, Nitrate, Nitrite, Selenium, TDS, Turbidity, Perfluorooctanoic acid (PFOA), Perfluorooctane sulfonate (PFOS), Organic chemicals, VOCs, alachlor, atrazine, benzene, carbofuran, carbon tetrachloride, chlorobenzene, chloropicrin, 2,4-D, dibromochloropropane (DBCP), o-dichlorobenzene, p-dichlorobenzene, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,2-dichloropropane, cis-1,3-dichloropropylene, dinoseb, endrin, ethylbenzene, ethylene dibromide (EDB), Bromochloroacetontrile, Dibromoacetontrile, Dichloroacetontrile, Trichloroacetontrile, 1,1-dichloro-2-propanone, 1,1,1-trichloro-2-propanone, heptachlor (H-34, Heptox), heptachlor epoxide, hexachlorobutadiene, hexachlorocyclopentadiene, lindane, methoxychlor, pentachlorophenol, simazine, styrene, 1,1,2,2-tetrachloroethane, tetrachloroethylene, toluene, 2,4,5-TP (silvex), tribromoacetic acid, 1,2,4-trichlorobenzene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, Trihalomethanes (THMs), Bromodichloromethane, Bromoform, Chloroform, Chlorodibromomethane, Xylenes, cyst, perchlorate, radium, selenium, chloramine, chlorine, meprobamate, phenytoin, atenolol, carbamazepine, TCEP, TCPP, DEET, Metolachlor, trimethoprim, ibuprofen, naproxen, estrone, bisphenol A, linuron, nonyl phenol
This filter is certified by IAPMO against NSF standards 42, 53, 58, 401, and P473 for claims specified on the Performance Data Sheet.
NSF/ANSI 42 – Reduction of aesthetic contaminant concerns such as chlorine, taste and odor, and chloramine.
NSF/ANSI 53 – Over 50 health-related contaminant reduction claims.
NSF/ANSI 401 – Removal of 15 specific contaminants related to prescription drugs, over-the-counter medications, herbicides, pesticides, and chemical compounds.
NSF/ANSI P473 – Remove per- and polyfluoroalkyl substances (PFAS) from drinking water.
NSF/ANSI 58 – Reverse osmosis (RO) water treatment systems that remove a wide range of contaminants
Pre/Carbon Filter Part replace every 6 months or 600 gallons.
Reverse Osmosis Membrane Part replace every 24 months or 1200 gallons.
VOC filter Part replace every 12 months or 600 gallons.
VOC Carbon with PH+Mineral Boost filter replace every 12 months or 600 gallons.
Certified by IAPMO against NSF/ANSI standard 58. The only tankless RO that has 3rd party certifications and a contaminant specification sheet detailing removal rates. Available in 600 and 800 gallon/day models.
This filter is certified by IAPMO to NSF/ANSI 58 for TDS reduction. This filter is also independently tested to reduce the below contaminants. For more details on removal rates see the Performance Data Sheet.
Mercury, Lead, Arsenic, Barium, Cadmium, Chromium, Copper, Fluoride, Nitrate, Selenium, TDS, Turbidity, Perfluorooctanoic acid (PFOA), Perfluorooctane sulfonate (PFOS), Organic chemicals, VOCs, alachlor, atrazine, benzene, carbofuran, carbon tetrachloride, chlorobenzene, chloropicrin, 2,4-D, dibromochloropropane (DBCP), o-dichlorobenzene, p-dichlorobenzene, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,2-dichloropropane, cis-1,3-dichloropropylene, dinoseb, endrin, ethylbenzene, ethylene dibromide (EDB), Bromochloroacetontrile, Dibromoacetontrile, Dichloroacetontrile, Trichloroacetontrile, 1,1-dichloro-2-propanone, 1,1,1-trichloro-2-propanone, heptachlor (H-34, Heptox), heptachlor epoxide, hexachlorobutadiene, hexachlorocyclopentadiene, lindane, methoxychlor, pentachlorophenol, simazine, styrene, 1,1,2,2-tetrachloroethane, tetrachloroethylene, toluene, 2,4,5-TP (silvex), tribromoacetic acid, 1,2,4-trichlorobenzene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, Trihalomethanes (THMs), Bromodichloromethane, Bromoform, Chloroform, Chlorodibromomethane, Xylenes
This filter was tested and certified by IAPMO to NSF/ANSI Standards 42, 53, and 58 for the claims specified on the Performance Data Sheet.
NSF/ANSI 42 – Reduction of aesthetic contaminant concerns such as chlorine, taste and odor, and chloramine.
NSF/ANSI 53 – Over 50 health-related contaminant reduction claims.
NSF/ANSI 58 – Reverse osmosis (RO) water treatment systems that remove a wide range of contaminants.
Smart faucet and filter life indicators that notify you when the filter needs to be changed out. The pre-filter has a 6 month lifetime. The carbon block has a 1 year lifetime. The RO has a 2-year lifetime. Model is available in 600 and 800 gallon/day flow.