Honest Water Filter’s Gold Plus high-capacity whole-house water treatment system treats up to 530,000 gallons. The high-capacity cartridge system is NSF certified. The sub-micron (0.2) filter also reduces 99.95% of microbial cyst-like cryptosporidium, toxoplasma, giardia and entamoeba that are resistant to public water disinfection and could cause health issues, the company points out.