Reverse osmosis systems · 9 models · 3 series

Microline RO Replacement Filters

Find RO replacement filters and manuals by selecting your Microline system below

We carry a large selection of authentic Microline RO replacement filters, membranes and cartridges. Microline is a trusted name in water purification solutions. With a legacy of excellence, Microline specializes in advanced filtration technology, delivering clean, safe, and great-tasting water for homes and businesses.

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Microline 3-Stage Models

4 models

Microline 4-Stage Models

2 models

Microline TFC 4-Stage Models

3 models

FAQ

Commonly Asked Questions about Microline RO Systems and Replacement Filters

Which Microline model families are represented on this page?

ESP Water carries parts for several Microline CTA and TFC families, including 14D/25D, 14S/25S, TFC-300, TFC-335, TFC-400, TFC-400-ESP, and TFC-435. The correct kit depends on the exact model and stage layout.

What is the difference between Microline CTA and TFC systems?

CTA and thin-film composite membranes use different materials and can have different feed-water requirements. Do not replace one membrane type with the other unless the complete system configuration and pretreatment are designed for it.

How do I choose a Microline kit with or without a membrane?

Select a kit with the membrane when that component is due or tested performance has declined. Choose the no-membrane kit for routine prefilter and postfilter service when the existing membrane still meets output and rejection targets.

Why do Microline filter lengths and fittings matter?

Several Microline cartridges are proprietary sizes such as 2 by 11.5 or 12 inches, and inline filters may have model-specific quick-connect fittings. Match part number, dimensions, and connection style.

How often should Microline filters be changed?

Sediment and carbon filters are commonly changed every 6–12 months and membranes about every 2–3 years, but follow the schedule for the exact model and adjust based on feed water, use, and performance.

Can one Microline replacement kit fit every TFC model?

No. TFC-300, 335, 400, 400-ESP, and 435 systems can use different stage counts, membrane ratings, cartridge formats, or fittings. Verify the model label and package contents.

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