I currently have an Aquasana AQ-4000 counter-top water filter.  The water quality is very good but I’ve had similar problems to other AQ-4000 owners with hassle and problems when replacing filters.  My last filter replacement left the unit leaking and I have been unable to stop the leaks.  As others have noted, the quality of the filtration is good but the quality of the housing leaves something to be desired.  So I’ve been researching other counter-top water filters to find a better replacement.

Certifications

I’ve gathered links to the relevant certifications for water filters.  For my purposes I would like to get a filter that meets the NSF/ANSI 42 & 53 certifications as well as the California Certification.

• NSF/ANSI Standard 42 – aesthetic or non-health-related contaminants (chlorine, taste and odor, and particulates)
• NSF/ANSI Standard 53 – health-related contaminants, such as Cryptosporidium, Giardia, lead, volatile organic chemicals (VOCs), MTBE (methyl tertiary-butyl ether)
• NSF/ANSI Standard 58 – reverse-osmosis treatment including fluoride, hexavalent and trivalent chromium, total dissolved solids, nitrates
• California Certification (CDPH) – organic chemicals, heavy metals, microbiological contaminants

Filters

• Aquasana AQ-4100 – $100, NSF 42 & 53, California Certification, 500 gallons
• NSF Claims
• chlorine, particulate, taste and odor
• asbestos, cyst, lead, mercury, mtbe, turbidity, voc
• Paragon P3200 – $100, NSF 42 & 53, California Certification, 500 gallons
• NSF Claims
• chloramine, chlorine, particulate, taste and odor
• cyst, lead, mercury, mtbe, turbibity, voc
• WaterChef C7000 – $160, NSF 42 & 53, California Certification, 800-1000 gallons
• NSF Claims
• chlorine, cloramine, particulate, taste and odor
• cyst, lead, mtbe, voc
• sold as BestFilters CTP200 (NSF Claims)
• sold as Essence AHW35
• Multi-Pure MPAD – $260, NSF 42 & 53, California Certification, 750 gallons
• NSF Claims
• chloramine, chlorine, particulate, taste and odor
• asbestos, chlordane, cyst, lead, mercury, mtbe, pcb, toxaphene, turbidity, voc
• Installation Video
• Multi-Pure MP880SC – $525, NSF 42 & 53, California Certification, plus NSF certified to reduce Arsenic, 600 gallons
• NSF Claims
• chloramine, chlorine, particulate, taste and odor
• asbestos, arsenic (pentavalent), chlordane, cyst, lead, mercury, mtbe, pcb, toxaphene, turbidity, voc

Conclusion

I think I’m leading toward the Multi-Pure MPAD.  It’s definitely more expensive than other options but seems to have much better performance in filtering contaminants.  That seems like a good trade-off, especially if the unit lasts a while.

More Reading

• California Certified Water Treatment Devices Directory