Large selection of replacement water filters, reverse osmosis membranes, testing kits and water filter system repair parts. From one water filter or membrane to case quantity discounts.

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Desal Reverse Osmosis Membranes ®

Desal Reverse Osmosis Membranes ®

Desal ® GE Osmonics Reverse Osmosis RO Membranes

Standard Size

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

  1. TDS Meter - Test For Total Dissolved Solids In Water - Reverse Osmosis Membrane Tester - TDS Meter
    TDS Meter - Test For Total Dissolved Solids In Water - Reverse Osmosis Membrane Tester - TDS Meter
    TDS Meter - Tester. The Only Way To Know If Your Reverse Osmosis RO Membrane Is Performing Correctly - Tests for TDS - Total Dissolved Solids. A Must For All RO System Owners. Compare Incoming Feed Water To Treated Water - Replace Membrane If Less Than 80% of TDS Is Being Removed - The lower the TDS level in the water, the more efficiently your body's cells actually get hydrated by the water that you drink. The higher the TDS levels in the water, the greater the probability of harmful contaminants that can pose health risks or hinder the absorption of water molecules on the cellular level. Simple to use for Reverse Osmosis membrane monitoring. We really like this tester and think that anyone who wants to know about the quality of their water should have one of these TDS Meter Testers to monitor their RO membrane. Learn More
    $49.99 Special Price $37.99 As low as $17.99
  2. Desal ® CTA-10 RO reverse osmosis membrane # 1201330 GE Osmonics Pentair
    Desal ® CTA-10 RO reverse osmosis membrane # 1201330 GE Osmonics
    Desal ® CTA-10 GE Osmonics - 10 GPD (gallons per day) CTA reverse osmosis RO membrane - standard size # 1201330 Learn More
    $69.99 Special Price $47.99 As low as $35.99
  3. Desal ® CTA-16 RO reverse osmosis membrane # 1201332 GE Osmonics Pentair
    Desal ® CTA-16 RO reverse osmosis membrane # 1201332 GE Osmonics

    Desal ® CTA-16 GE Osmonics - 16 GPD (gallons per day) CTA reverse osmosis membrane - standard size. # 1201332 - 1224433

    Learn More
    $69.99 Special Price $49.99 As low as $35.99
  4. DESAL - TFM-100 RO Reverse Osmosis Membrane -1000
    Desal ® TFM-100 RO reverse osmosis membrane # 1221122 GE Osmonics Pentair
    Desal ® TFM-100 GE Osmonics - 100 GPD (gallons per day) TFC Style RO reverse osmosis membrane - Fits Standard Size Membrane Housing. # 1221122. Pentair ® / GE Osmonics ® 100 GPD Thin Film Reverse Osmosis Membrane Model # TFM-100 - Part # 1221122. Compatible replaccement for Dow Filmtec, WaterFiltersOnline.com and CSM RO Reverse Osmosis membranes. Learn More
    $89.99 Special Price $64.99 As low as $49.99
  5. DESAL - TFM-18 RO Reverse Osmosis Membrane #1220188 GE Osmonics -1000
    Desal ® TFM-18/T112-18 RO reverse osmosis membrane # 1220188 GE Osmonics
    Desal ® TFM-18 GE Osmonics - 18 GPD (gallons per day) TFC Style reverse osmosis membrane - Fits Standard Size Membrane Housing. # 1220188. Pentair ® / GE Osmonics ® 18 GPD Thin Film Reverse Osmosis Membrane Model # TFM-18 - Part # 1220188. THE DESAL TFM-18 HAS BEEN DISCONTINUED AND IS NO LONGER AVAILABLE. IF YOU ORDER THE DESAL TFM-18 YOU WILL RECEIVE THE T112-18. Learn More
    $89.99 Special Price $49.99 As low as $39.99
  6. DESAL TFM-24 RO Reverse Osmosis Membrane #1220189 GE Osmonics Pentair - 1000
    Desal ® TFM-24/Filmtec TW30-1812-24 RO reverse osmosis membrane # 1220189 GE Osmonics Pentair
    Desal ® TFM-24 GE Osmonics - 24 GPD (gallons per day) TFC Style Reverse Osmosis RO Membrane - Fits Standard Size Membrane Housing. # 1220189. Pentair ® /G E Osmonics ® 24 GPD Thin Film Reverse Osmosis Membrane Model # TFM-24 - Part # 1220189. Compatible with Dow Filmtec, WaterFiltersOnline.com and CSM RO Reverse Osmosis membranes. THE TFM-24 HAS BEEN DISCONTINUED AND IS NO LONGER AVAILABLE. IF YOU ORDER THE TFM-24 YOU WILL RECEIVE THE FILMTEC TW30-1812-24. Learn More
    $89.99 Special Price $56.99 As low as $39.99
  7. DESAL- TFM-36 RO Reverse Osmosis Membrane #1220190 GE Osmonics- 1000
    Desal ® TFM-36 RO reverse osmosis membrane # 1220190 GE Osmonics
    Desal ® TFM-36 GE Osmonics - 36 GPD (gallons per day) TFC style reverse osmosis membrane - Fits Standard Size Membrane Housing. # 1220190 Learn More
    $69.99 Special Price $47.99 As low as $35.99
  8. DESAL TFM-50 RO Reverse Osmosis Membrane #1204694 GE Osmonics - 1000
    Desal ® TFM-50 RO reverse osmosis membrane # 1204694 GE Osmonics
    Desal ® TFM-50 GE Osmonics - 50 GPD (gallons per day) TFC style reverse osmosis membrane RO - Fits Standard Size Membrane Housing. # 1204694 Learn More
    $69.99 Special Price $49.99 As low as $35.99
  9. DESAL TFM-75 RO Reverse Osmosis Membrane #1204487 -1000
    Desal ® TFM-75 RO reverse osmosis membrane # 1204487 GE Osmonics
    Desal ® TFM-75 GE Osmonics - 75 GPD (gallons per day) TFC style RO reverse osmosis membrane - Fits Standard Size Membrane Housing. # 1204487 Learn More
    $69.99 Special Price $45.99 As low as $35.99
  10. 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
  11. 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. Learn More
    $33.99 Special Price $19.99 As low as $14.99
  12. 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). Learn More
    $34.99 Special Price $19.99 As low as $16.99
  13. Spanner Wrench To Fit Standard Size Membrane Housings
    Spanner Wrench To Fit Standard Size Membrane Housings
    Wrench To Fit Standard Size Membrane Housings. Easily open those stubborn reverse osmosis membrane housings. Learn More
    $17.99 Special Price $9.99 As low as $6.99
  14. 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. Learn More
    $17.99 Special Price $9.99 As low as $8.49
  15. Pro Products Sani System Sanitizer
    Pro Products Sani System Sanitizer
    Pro Products Sani System Sanitizer. 0.25 or 0.5 fl. oz. concentrate. 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. 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. Sani-System is now NSF certified!This is the best sanitizing solution available anywhere! Stock up and save. Learn More
    $7.99 Special Price $5.99 As low as $3.49
  16. JOHN GUEST- PI480821S- 1000
    John-Guest-Male-Conn-EL (John Guest PI480821S Fixed Elbow 1/4" Tube X 1/8" MNPT)
    John Guest PI480821S Fixed Elbow 1/4" Tube X 1/8" MNPT - SOLD IN PAIRS Learn More
    $4.99
  17. Fitting_elbow-1-4X1-8Membrane (Jaco Elbow Connector Fitting 1/4" Tube X 1/8" MNPT)
    Fitting_elbow-1-4X1-8Membrane (Jaco Elbow Connector Fitting 1/4" Tube X 1/8" MNPT)
    Jaco Elbow Connector Fitting 1/4" Tube X 1/8" MNPT Membrane Housing Size - SOLD IN PAIRS Learn More
    $4.99

Easy TDS Membrane Performence 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.


* Desal ® is the registered trademark of Desal, the manufacturer of Desal ® brand water treatment equipment.  The replacement filters and membranes listed above are not manufactured or endorsed by Desal.  Rather, these filters and membranes are manufactured by other companies.  While these filters and membranes are compatible for use in Desal ® 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 Desal ® equipment.