The standard replacement schedule for the UC-200 is after 5 years.
Filter life depends on incoming water quality. You must write down your installation date. Monitor performance with chlorine or contaminant-specific test strips. Do not use a TDS/PPM meter; it is not valid for this system.
If you notice a significant drop in water flow or a change in taste/odor before 5 years, replace the filter early. Excess sediment from galvanized pipes or high-sediment areas can shorten filter life.
Register your warranty with APEC Water. They recommend installing a sediment prefilter upstream if you have visible particulate matter or live in an area like parts of NY or NJ.