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Dow Filmtec Reverse Osmosis Membranes ®

Dow Filmtec Reverse Osmosis Membranes ®

Dow Filmtec ® TFC Replacement Reverse Osmosis RO Membranes - Standard Size

Find out how to increase the GPD capacity size of your membrane.

Dow Filmtec commercial membranes available.

  1. Flow_Restrictor-1000
    Inline reverse osmosis membrane flow restrictor
    Premium inline reverse osmosis membrane flow restrictor - Our in-line capillary flow restrictors are simple to install. Simply push the 1/4" poly tube firmly into the quick connectors and you are done. Be sure that you order the flow restrictor size to match your reverse osmosis membrane size. Arrow on side points toward the drain. Very simple to install.
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    $33.99 Special Price $19.99 As low as $14.99
  2. Standard Size RO Reverse Osmosis Membrane Housing
    Standard size RO reverse osmosis membrane housing
    Standard size RO reverse osmosis membrane housing - 90° Ports with 1/8" FNPT Threads - Includes New O-rings and 3 90° 1/4" Jaco Fittings For 1/4" O.D. Tube. Upgrade to the optional John Guest Quick Connectors. The end with a single port is the inlet feed water. On the end with two ports the center port is the permeate (product) water. The offset port is the brine (waste).
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    $34.99 Special Price $19.99 As low as $16.99
  3. O-rings For Standard Style RO Reverse Osmosis Membrane Housing
    O-rings For Standard Style RO Membrane Housing
    O-rings For Standard Style RO Membrane Housing. Pair of O-rings for standard style reverse osmosis membrane housings.
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    $17.99 Special Price $9.99 As low as $8.49
  4. TW30-1812 RO Membrane Housing- 304 Stainless Steel- SS-1812- 1000
    TW30-1812 Membrane housing - 304 Stainless Steel - SS-1812
    TW30-1812 Stainless Steel RO Membrane Housing - High detail and quality. This high end Stainless Steel RO Membrane Housing fits standard residential TW30-1812 RO membranes, which is the most common size of reverse osmosis membrane for home RO systems. This SS Membrane Housing is the finest quality housing we have ever seen for residential RO systems. Food Grade 304 Stainless Steel.
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    $129.99 Special Price $89.99
  5. Molykote-From DOw Corning- 111 Compound-6 Gram O-ring Silicone Lubricant & Sealant-Dow-111-5-gram-1000
    Dow Corning (Molykote) ® 111 6 gram O-ring Silicone Lubricant and Sealant - Be sure to lube your O-rings to help prevent leaks.
    Dow Corning/Molykote ® 111 6 gram O-ring Silicone Lubricant and Sealant - 6 gram pillow pack. (like a ketchup packet) Great O-ring sealant and lubricant. FDA and NSF approved. (Do Not Use Petroleum Jelly As It May Break Down O-rings Or Housings) This is the same premium grade silicone sealant and lubricant used in underwater photography cameras, scuba gear and other underwater applications that simply can't afford leaks. Why not use the best for your reverse osmosis or drinking water filtration system?

    Dow 111 Silicone MSDS Safety Sheet

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    $5.99 Special Price $3.99 As low as $1.79
  6. Pro Products Sani System Water Filtration System Sanitizer
    Pro Products Sani System Water Filtration System Sanitizer
    Sani-System ® Pro Products is proud to introduce Sani-System, the first and only EPA product approved for sanitizing water softeners, RO units and Water Coolers. Alos NSF certified. Sani System is proven to kill 99.9% of E. coli, E. coli O157:H7, Staphylococcus aureus, Listeria monocytogenes and other harmful bacteria. It does not use chlorine, other oxidizers or acids that can harm water softener equipment parts. Use is simple; each dose comes in a pre-measured pouch. Just cut, pour and regenerate softener. No measuring, No mess! Sanitizing Equipment! Applications Interior Surfaces of Water Softeners, Reverse Osmosis (RO) Units, Ice Machines, Water Coolers, Water Holding Tanks and Pressure Tanks. Pro Products Sani System Sanitizer. 0.25 fl. oz. concentrate is perfect for your RO reverse osmosis drinking water system sanitizing..
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    $7.99 Special Price $4.99 As low as $2.49

Easy TDS Membrane Performance Calculator
See If It is Time To Replace Your Membrane

Simply enter your Feed Water TDS and RO Water TDS into the boxes above and click "Submit". The percentage of TDS Rejection will be displayed. We normally recommend membrane replacement once you drop below 75%. This may vary in areas with high TDS in the feed water.

See our selection of TDS meters under Water Tests


Be sure to check our Parts Department for important parts such as TDS Testers For Reverse Osmosis Membranes, Replacement Tanks, O-rings , Filter Housing Wrenches, Faucets, Pumps, Fittings, UV Systems and more parts for your reverse osmosis pure water filtration system.   View maintenance and servicing tips online at our Installation & Trouble shooting Guide.


* Dow Filmtec ® is the registered trademark of Dow, the manufacturer of Dow Filmtec ® brand water treatment equipment. The replacement filters and membranes listed above are not manufactured or endorsed by Dow Filmtec. Rather, these filters and membranes are manufactured by other companies. While these filters and membranes are compatible for use in Dow Filmtec ® brand water treatment equipment, we make no representation as to whether using these filters and membranes is consistent with the warranty and specifications applicable to Dow Filmtec ® equipment.