It depends on your water quality, but a general guideline for many household filters (sediment cartridges, basic pre-filters) is to clean or replace them every 3–6 months. In areas with very dirty or sandy water, you might need attention even sooner; you’ll notice pressure dropping or the filter looking visibly brown or grey.
Follow the manufacturer’s instructions for your specific filter model. Some are designed to be washed and reused several times; others are strictly “replace only.” Ignoring them for too long turns them from protectors into blockages – instead of stopping particles, they just restrict flow and make pumps or appliances work harder.
Check transparent housings occasionally. If you see heavy discoloration, sludge or trapped debris, don’t wait for a calendar reminder. Changing filters on time also protects downstream devices like RO systems, geysers, washing machines and taps from unnecessary wear.
Think of filters as sacrificial guards: they collect the dirt so your pipes and machines don’t have to. But they can’t do that job forever without a refresh.