Membrane Replacement When Purification Quality Drops
The membrane is the core purification stage of an RO system, and it's the part that quietly degrades with age — scaling, fouling and normal wear all reduce its rejection rate over time. If your output TDS is creeping close to your source TDS, or flow has dropped even with clean pre-filters, the membrane is usually the reason. We test before replacing, so you're not paying for a membrane change the unit doesn't actually need.
Common signs you need membrane
How our membrane process works
TDS rejection test
We compare source and output TDS to confirm the membrane, not another part, is the cause.
Membrane selection
A membrane matched to your system's capacity and stage count is chosen — over- or under-spec membranes hurt performance.
Fitting & flushing
The new membrane is fitted and flushed for the manufacturer-recommended cycles before use.
Rejection re-test
TDS rejection is re-measured to confirm the membrane is performing to spec.
Frequently asked questions
How do I know if my RO needs a new membrane?
The clearest sign is output TDS rising closer to your source water TDS. We test this on-site free of cost before recommending a membrane change.
How long does a membrane usually last?
Typically 18–24 months for domestic use, shorter for high-TDS source water or heavy commercial usage, and longer if pre-filters are changed on schedule.
Is membrane replacement more expensive than filter replacement?
Yes, membranes cost more than sediment or carbon filters since they're the primary purification component, but they're needed far less often.