American Water FiltrationServing the USA & World Since 1999

Nugen Reverse Osmosis Systems Replacement Water Filters

Nugen RO-5-50, RO-3-25, Microline TFC-435 and GE Merlin Reverse Osmosis Compatible Premium Replacement Water Filters and RO Reverse Osmosis Membranes.

Replacement water filters, faucets, accumulator holding water tanks, water filter cartridges, RO membranes, O-rings, Filter Housing Spanner Wrenches, Valves, Water Pumps and reverse osmosis drinking water system replacement parts.

Easy TDS Membrane Performance Calculator
See If It is Time To Replace Your Membrane

Simply enter your Feed Water TDS and RO Water TDS into the boxes above and click "Submit". The percentage of TDS Rejection will be displayed. We normally recommend membrane replacement once you drop below 75%. This may vary in areas with high TDS in the feed water.

See our selection of TDS meters under Water Tests

Be sure to check our Parts Department for important replacement parts for your Nugen RO-5-50, RO-3-25, GE Merlin and TFC-400 Reverse Osmosis System such as TDS Testers For Reverse Osmosis Membranes, Replacement Tanks, O-ringsFaucets, Pumps, Fittings, UV Systems and more service parts for your reverse osmosis pure water filter system.   View maintenance and servicing tips for Nugen RO-5-50, RO-3-25, GE Merlin or TFM-400 drinking water filter system online at our Installation & Trouble Shooting Guide.

*Nugen RO-5-50, RO-3-25 ® are the registered trademarks of Nugen, the manufacturer of Nugen RO-5-50 and RO-3-25 brand drinking water filtration equipment.  The replacement water filters and reverse osmosis membranes listed above are not manufactured or endorsed by Nugen.  Rather, these replacement filters and RO membranes are manufactured by other companies.  While these filters and membranes are compatible for use in Nugen RO-5-50, RO-3-15, T.F.C.435 and GE Merlin reverse osmosis water filtration equipment, we make no representation as to whether using these water filters and RO membranes is consistent with the warranty and specifications applicable to Nugen RO-5-50, RO-3-15, T.F.C.435 and GE Merlin equipment.