Water filters do not last forever. Over time, they become saturated with the contaminants they have been removing, and their effectiveness drops. Eventually, a clogged or exhausted filter can actually make your water worse by releasing trapped contaminants or harboring bacteria.
Knowing when to replace each filter in your system is essential for maintaining water quality and protecting your equipment.
Replace every 3-6 months
Sediment filters are the first line of defense, catching sand, silt, rust, and particles before they reach the rest of your system. In South Florida, where water often carries significant sediment, these filters can clog faster than in other regions.
Check monthly: If the filter looks brown or dark, or if you notice reduced water pressure throughout your home, it is time for a change regardless of the schedule.
Replace every 6-12 months (or per manufacturer specs)
Carbon filters remove chlorine, chloramine, taste, odor, and many organic chemicals. The carbon becomes saturated over time and loses its absorption capacity. Some whole-house carbon systems use large media tanks that only need media replacement every 3-5 years, while cartridge-style filters need changing more frequently.
Replace every 10-15 years
The resin beads inside a water softener regenerate with salt, so they last much longer than disposable filters. However, chlorine exposure, iron fouling, and normal wear eventually degrade the resin. Signs of failing resin include water that feels hard despite having salt in the tank, or small beads appearing in your water.
RO systems have multiple filter stages, each with its own schedule:
Critical: Never skip the pre-filter changes. Their job is to protect the expensive RO membrane. If pre-filters are neglected, chlorine and sediment will destroy the membrane prematurely.
Replace annually
UV lamps lose intensity over time, even if they still appear to be working. After 12 months of continuous use, the UV output drops below the level needed to reliably kill bacteria and viruses. The quartz sleeve should also be cleaned annually.
Replace every 6 months
These small carbon filters have limited capacity and degrade quickly. If you have an RO system connected to your fridge, you can skip the refrigerator filter entirely since the RO provides far superior filtration.
Do not rely solely on the calendar. Watch for these signs that a filter change is overdue:
A clogged sediment or carbon filter restricts water flow. If pressure drops at multiple fixtures, check your whole-house filters first.
If water that used to taste clean starts tasting like chlorine, chemicals, or minerals, your carbon filter is likely exhausted.
Sediment filters that have reached capacity allow particles through. If your water looks hazy or has visible particles, change the filter immediately.
If your RO faucet used to flow steadily but now drips slowly, the pre-filters or membrane are due for replacement. A TDS meter can confirm whether the membrane is still performing.
If your ice starts looking cloudy or tasting off, check both your refrigerator filter and any whole-house filters.
Skipping filter changes does not save money. Here is what it costs you:
The simplest way to stay on schedule is a professional maintenance plan. Our plans include:
If it has been a while since your last filter replacement, or you are not sure what schedule your system requires, contact us to schedule a service visit. We service all major brands and system types.
Schedule a free water test and get personalized recommendations for your home.
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