When & How to Change Each Filter Type

Manufacturer replacement intervals are set so the filter removes what the certification claims for the whole period. A tired carbon block can still taste fine while breakthrough starts.

If the remove bucket is a certified RO or carbon system marked NSF/ANSI 53 or 58, treat the rated capacity as a hard limit, not a soft hint.

Typical rated life is 3–6 months or based on throughput. If your water has visible sediment, check earlier — a clogged pre-filter only gets worse.

Replace the pre-filter even if the main RO membrane still measures fine.

Most household carbon blocks are rated 6 months to 1 year. Flow rate and chlorine taste are rough signals, but they are not certification data.

Pre-flush the new cartridge per the manual (usually a few minutes of run-to-drain) before you drink the water.

RO membranes are commonly rated 12–24 months. A drop in tank pressure, an increase in dissolved solids, or water that starts to taste flat are signs to check the makers’ guidance.

Do not stretch beyond the rated months unless you monitor with a TDS meter and the numbers stay in range.

UV bulbs have a runtime-based end-of-life. Post-carbon and mineralizing cartridges are on the same replace-schedule logic as the main carbon block.