PuROLine PL40T36PP 4-Stage RO Replacement Filters

Start by clicking on the photo of your PuROline system above. From there, you can add the needed filters to your cart. In some cases, you can save time by ordering all of the needed filters in one "filter kit". Remember that the RO membrane usually only needs to be replaced every two years, while the sediment and carbon filters are replaced every 6-12 months depending on water usage and water quality.

For instructions on installing the membrane and filters, select your specific model above. Look for owner's manuals or installation guides. Check out our general RO filter replacement instructions.

Check the model number on your PuROLine system label. Then choose the corresponding filter kit on ESPWaterProducts.com. Each system has its own page showing the correct filters and membranes. For example:

• PuROLine PL40T36PP Four-Stage RO System
• PuROLine PL50T50 Five-Stage RO System
• PuROLine PL50T100 RO Replacement Filter Kit with Membrane

These pages list the 1-year replacement filter kits and compatible membranes for each PuROLine model.

Your PuROline reverse osmosis filters and membrane can remove common pollutants from water including pesticides, sulfates, fluoride, nitrates, lead, pharmaceuticals, arsenic and more. The RO system's carbon filter will also remove chloramines and chlorine.

Learn more about what contaminants can be removed with reverse osmosis filtration.

Most PuROLine reverse osmosis systems require sediment and carbon pre-filters to be replaced every 6–12 months, depending on water usage and source water quality. The RO membrane typically lasts around 2 years.

For a full schedule and checklist, see the ESP Water Reverse Osmosis Maintenance Guide , which explains how often to replace carbon, sediment, and GAC filters.

PuROLine filters use standard RO cartridge sizes, but replacement kits are matched to specific PuROLine models. ESP Water lists filters and parts by model on their PuROLine Reverse Osmosis Systems collection page .

Most PuROLine systems use 1812-style thin-film composite (TFC) membranes in the 36–50 gallons-per-day (GPD) range. For example:

• The PL40T36PP system uses a 36 GPD membrane such as the PuROLine PL40T36 Replacement Filter Kit (membrane sold separately) , which references a 36 GPD RO membrane.
• The PL50T50 system uses a 50 GPD membrane like the PuROLine PL50T50 Five-Stage RO System , which lists the compatible 50 GPD membrane and parts.

You can also browse the RO Membranes collection to see typical GPD ratings and performance details.

Common signs include:

• Slow flow or reduced water pressure at the RO faucet
• Bad taste or odors returning to the water
• Cloudy or “milky” water or ice

If you notice any of these, your filters may be overdue. ESP Water’s guides on reverse osmosis maintenance and how to change RO filters and membranes provide step-by-step instructions and replacement timelines.

In many cases you can, as long as the replacement filters have the same physical size and connection type as the originals (for example, 2.5" × 10" sediment and carbon cartridges plus an 1812-style RO membrane). However, using PuROLine-matched kits from ESP Water ensures everything is compatible.

To see the exact filter sizes and styles your system uses, start with the PuROLine RO Replacement Filters collection and model-specific filter kits such as the PL40T50 RO Replacement Filter Kit (Membrane Sold Separately) .