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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Natures Way Reverse Osmosis

Natures Way Reverse Osmosis

Nature's Way ® Compatible Replacement Water Filters & TFC Reverse Osmosis Membranes - 4 Stage System

2 vertical filter housings, one top mounted horizontal inline GAC carbon post filter and one top mounted standard size horizontal RO membrane housing.

  1. PENTEK- #151121- Slim-Line Water Filter Housing Replacement - 1000
    Pentek # 151121 O-Ring For Slim Line Water Filter Housing Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek # 151121 O-Ring For Slim Line Water Filter Housing Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. O-Ring For Slim Line Water Filter Housing. Buna-N FDA Grade. (Slim Line Housings Use A 3 1/2" diameter "O" Ring) Ametek # 151121 Same as Culligan OR-38 O-ring. Learn More
    $5.69 Special Price $4.99 As low as $3.00
  2. Pentek SW-1A # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench
    Pentek SW-1A # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek SW-1 # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. SW-1 Water Filter Housing Wrench. Fits 4" Slim Line Housings. (Slim Line Housings Have A 3 1/2" diameter "O" Ring) Ametek # 150294 Only for use in loosening filter housings, never to tighten. Overtightening may cause damage to the O-rings and make re-opening VERY difficult. Hand tighten only. Fits most standard style RO systems. Replaces 150294. For really stubborn filter housings our technicians will use two wrenches together for maximum power where one wrench might break or not do the job. Our techs know the tricks. Order New O-rings And Be Sure To Lube Them With Dow 111 Silicone Sealant To Prevent Leaks Learn More
    $9.99 Special Price $6.99 As low as $4.99
  3. GE Osmonics ® Purtrex PX-5-978 Sediment Replacement Water Filter # 93023
    GE Osmonics ® Purtrex PX-5-978 Sediment Water Filter # 93023
    GE Osmonics ® Purtrex PX-5-978 5 Micron Sediment Water Pre Filter. True-graded density pure polypropylene depth replacement water filter. # 93023 9 7/8" long X 2 1/2" diameter. 40 per case, sold individually. Order a case and save even more. Learn More
    $8.99 Special Price $5.99 As low as $3.99
  4. 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 $4.99 As low as $2.49
  5. 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
  6. TDS Meter Inline Water Tester DM1 - HM Digital Dual Mode Reading
    TDS Meter Inline Tester- Dual Mode Reading - Easily Installs Inline - Very Simple To Use
    TDS Meter - Dual Mode - Installs Inline - Check the TDS level with the push of a button. Now you can easily check to make sure the water from your reverse osmosis system is top quality. Measure the tap water coming in vs. the purified water going out of your system at any time. Very easy installation. FEATURES Displays TDS levels of the feed water and product water with in & out electrode probes. Highly efficient and accurate due to its advanced microprocessor technology. Auto-Off function conserves battery power. The unit shuts off automatically after 10 minutes of non-use. Comes equipped with John Guest Quick-Connect T-fittings as shown. Installs quickly and easily. SPECIFICATIONS Range: 0-9990 ppm Accuracy: ±2% Always know if your RO membrane is performing correctly! Learn More
    $49.99 Special Price $39.99 As low as $19.99
  7. DOW FILMTEC -  TW30-1812-50 RO Reverse Osmosis Membrane #80722-1000
    Dow Filmtec ® TW30-1812-50 RO reverse osmosis membrane # 80722
    Dow Filmtec ® TW30-1812-50 TFC 50 GPD RO reverse osmosis membrane - standard size 1.75" X 11.75" Part # 80722 Learn How To Upgrade Your Reverse Osmosis Membrane Capacity Learn More
    $84.99 Special Price $69.99 As low as $54.99
  8. Air Pressure Gauge for Reverse Osmosis Water Accumulator Tanks -1000
    Air pressure gauge for reverse osmosis water accumulator tanks
    Air pressure gauge for reverse osmosis water accumulator tanks - Specially calibrated for reverse osmosis system tanks. Scale from 1 to 20 PSI. Large scale reading over small PSI range allows optimum accuracy. Just like car tires lose air pressure, so does the bladder of your reverse osmosis water accumulator tank. Improper tank air pressure will cause your system to operate improperly. This is a must for all reverse osmosis system owners. Learn More
    $24.99 Special Price $17.99 As low as $12.99
  9. 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
  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

    Learn More
    $5.99 Special Price $3.99 As low as $1.79
  11. DOW FILMTEC - TW30-1812-100 HR RO Reverse Osmosis Membrane 170102- 1000
    Dow Filmtec ® TW30-1812-100 HR RO reverse osmosis membrane
    Dow Filmtec ® TFC 100 GPD RO reverse osmosis membrane - standard size 1.75" X 11.75" Extra fast recovery and high production flow rate.

    Learn How To Upgrade Your Reverse Osmosis Membrane Capacity

    Learn More
    $129.99 Special Price $84.99 As low as $59.99
  12. DOW FILMTEC TW30-1812-24 RO #93430 Reverse Osmosis Membrane- 1000
    Dow Filmtec ® TW30-1812-24 RO reverse osmosis membrane # 93430

    Dow Filmtec ® TW30-1812-24 24 GPD TFC RO reverse osmosis membrane - standard size 1.75" X 11.75" Part # 93430

    Learn More
    $89.99 Special Price $56.99 As low as $37.99
  13. DOW FILMTEC - TW30-1812-36 #80719 RO Reverse Osmosis Membrane-1000
    Dow Filmtec ® TW30-1812-36 RO reverse osmosis membrane # 80719
    Dow Filmtec ® TW30-1812-36 TFC 36 GPD RO reverse osmosis membrane - standard size 1.75" X 11.75" Part # 80719 Learn More
    $99.99 Special Price $59.99 As low as $39.99
  14. DOW FILMTEC TW30-1812-75 (BW60-1812-75) #114731 RO Reverse Osmosis Membrane- 1000
    Dow Filmtec ® TW30-1812-75 (BW60-1812-75) RO reverse osmosis membrane # 114731
    Dow Filmtec ® TW30-1812-75 (BW60-1812-75) TFC 75 GPD RO reverse osmosis membrane - standard size 1.75" X 11.75" Part # 114731 Learn More
    $119.99 Special Price $74.99 As low as $49.99
  15. 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
  16. GOES GREEN- Premium 5 Micron Coconut Carbon Block Filter- 1000
    Goes Green 5 Micron Premium Coconut Carbon Block
    Goes Green 5 Micron Premium Extruded Carbon Block Water Filter provides optimal VOC reduction and high chemical absorptive capacity. 9 3/4" long X 2 1/2" diameter OD X 1 1/4" diameter ID. 25 per case, sold individually. Order a case and save even more. Learn More
    $23.99 Special Price $15.99 As low as $11.99
  17.  Inversion Tank Stand Reverse Osmosis System
    Inversion Tank Stand Reverse Osmosis System
    Protect the bladder of your tank by using our tank inversion stand. Most tanks hold the water in the top portion of the tank instead of the bottom. Storing the water on top of the bladder adds the weight of the water to the pressure to cause unnecessary stress on the bladder. By inverting (turning upside down) it removes the weight of the water on the seal where the bladder is attached to the inside of the tank. Fits most standard 3 and 4 gallon tanks. Plastic Inversion RO Tank Stand. UPC #850901003408 Learn More
    $27.99 Special Price $17.99
  18. GGN-Faucet-AG-P-Chrome Air Gap Faucet-Long Reach-1000
    $39.99 Special Price $29.99
  19. 4 Gallon Reverse Osmosis Tank GGN-Tank-4-Pro-3.2
    4 Gallon Reverse Osmosis Tank GGN-Tank-4-Pro-3.2
    GGN-Tank-4 - 4 Gallon RO Reverse Osmosis Tank 1/4" NPT Threads. Stainless Steel connector. This is the perfect replacement tank for most residential RO Reverse Osmosis systems. Set Air Pre Charge To 7 psi With The Tank Empty Blue color. UPC #850901003491 Learn More
    $79.99 Special Price $49.99
  20. GGN-10-2-1000
    GGN-10-2-Block Premium Quality Carbon Block Replacement Water Filter
    10 Micron Premium Carbon Block Filter. Replaces KX Carbon Block Water Filter # 10-250-190-975 Compatible Replacement. The perfect carbon block for your standard reverse osmosis system. Extruded Carbon Block Water Filter. 9 3/4" long X 2 1/2" diameter OD X 1 1/4" diameter ID. 20 per case, sold individually. Order a case and save even more. GGN-10-2-BLOCK Learn More
    $12.99 Special Price $9.99 As low as $7.79

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.


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