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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Nature's Way Backpack Water Filters

Nature's Way Backpack Water Filters

Nature's Way ® Backpack compatible replacement water filters and RO reverse osmosis membranes

  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. 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
  3. 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
  4. 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
  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. 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

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    $89.99 Special Price $56.99 As low as $37.99
  7. 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
  8. Omnipure CL10PF5 - Inline 5 Micron Inline Sediment Replacement Water Filter- 1000
    Omnipure ® CL10PF5 inline 5 micron inline sediment replacement water filter
    Omnipure ® CL10PF5 inline 5 micron sediment water filter replacement cartridge. 1/4" (-B) or 3/8" (-C) FNPT (Female National Pipe Thread) connections. Replacement Jaco connectors and John Guest Speedfit connectors availble seperately for 1/4" or 3/8" tube. 25 per case, priced and sold individually. Order a case and save even more. Learn More
    $19.99 Special Price $10.99 As low as $8.99
  9. Omnipure CL-10RO-T/33 GAC Inline Replacement Water Filter-1000
    Omnipure ® CL-10RO-T/33 GAC Inline Water Filter
    Omnipure ® CL-10RO-T/33 GAC - 10" X 2" Carbon Inline Replacement Post Water Filter - GAC (granular activated carbon) Acid Washed Carbon - Should be changed at least every 12 months. 25 per case, sold individually. Order a case and save even more. Learn More
    $21.99 Special Price $11.99 As low as $9.49
  10. Omnipure ® CL-10RO-T/40 GAC Inline Replacement Water Filter With Coconut Shell
    Omnipure ® CL-10RO-T/40 GAC Inline Replacement Water Filter With Coconut Shell
    Omnipure ® CL-10RO-T/40 inline GAC carbon water filter replacement cartridge with Coconut Shell for best taste. 1/4" (-B) or 3/8" (-C) FNPT (Female National Pipe Thread) connections. Replacement Jaco connectors and John Guest Speedfit connectors availble seperately for 1/4" or 3/8" tube. 25 per case, priced and sold individually. Order a case and save even more. Learn More
    $25.99 Special Price $14.99 As low as $12.49

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.