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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Standard Size Reverse Osmosis RO System Filters

Standard Size Reverse Osmosis RO System Filter Change Replacement Cartridges
  1. Standard Four Stage RO Reverse Osmosis Water Filter Change Kit- 1000
    Four Stage Standard RO Water Filter Change Kit
    Four Stage Standard RO Reverse Osmosis Water Filter Change Kit. One Year Filter Change Kit: (2) 5 Micron Poly Spun Sediment Pre Filters (9 7/8") (1) 10 Micron Extruded Carbon Pre Filter (9 3/4") (1) In-Line GAC Post Filter (Granular Activated Carbon 10") The sediment prefilter needs changed twice as often as the carbon filters, so our kit includes an extra one. RO Membranes are sold separately. Learn More
    $39.99 Special Price $33.99 As low as $27.99
  2. Standard Five Stage RO Reverse Osmosis Water Filter Change Kit-1000
    Five Stage Standard RO Water Filter Change Kit
    Five Stage Standard RO Water Filter Change Kit - One Year Filter Change Kit: (2) 5 Micron Poly Spun Sediment Pre Filters (9 7/8") (2) 10 Micron Extruded Carbon Pre Filter (9 3/4") (1) In-Line GAC Post Filter (Granular Activated Carbon 10") FREE CARBON BLOCK UPGRADE - Our 5 stage filter replacement kit has a second carbon block pre filter to replace the GAC hard shell pre filter that comes standard in most RO systems. The sediment prefilter needs changed twice as often as the carbon filters, so our kit includes an extra one. Membranes are sold separately. LIMITED TIME OFFER - Omnifilter prefilters and post filter for additional savings. The Omnifilter post filter is only available for post filters using 1/4" quick connections. Learn More
    $54.99 Special Price $43.99 As low as $35.99
  3. 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
  4. 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
  5. 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
  6. 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
  7. 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

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    $129.99 Special Price $84.99 As low as $59.99
  8. 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