The bigger picture
About this topic
Reverse osmosis uses a membrane to produce treated water and a separate concentrate stream. An under-sink system usually serves a particular drinking-water outlet, and its complete model may include several other stages.
Compare the claim and the daily work
Check the reduction claim you need, the incoming-water requirements, delivery, drain connection, and service access. EPA WaterSense labeling is a separate check for eligible point-of-use models, not a certification that every possible concern has been addressed.
Keep the manual’s replacement requirements for each stage. Start with the RO efficiency guide, then use the maintenance articles below for equipment you already own.
