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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  1. 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.
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    $54.99 Special Price $43.99 As low as $35.99
  2. 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.
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    $23.99 Special Price $15.99 As low as $11.99
  3. 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 Replacement Water Filter Change Kit.   (2) 5 micron sediment Pre Filters, (1) 10 micron Carbon Block Filter and (1) Inline GAC Post Filter.  RO reverse osmosis membranes sold separately.  

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    $39.99 Special Price $33.99 As low as $27.99
  4. KX Matrikx ® 10/2 Carbon Block Water Filter # 10-250-190-975 Replacement-1000
    KX Matrikx ® 10/2 Carbon Block Water Filter # 10-250-190-975

    The KX 10/2 has been discontinued. If you order the KX 10/2 you will receive the GGN 10/2 Carbon Block Filter. 9 7/8" 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 How To Upgrade Your Reverse Osmosis Membrane Capacity

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    $17.99 Special Price $9.99 As low as $6.99
  5. 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.
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    $8.99 Special Price $5.99 As low as $3.99
  6. 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
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    $12.99 Special Price $9.99 As low as $7.79
  7. Omnipure CL-10RO-T/33 GAC Inline Replacement Water Filter-1000
    Omnipure ® CL-10RO-T/33 GAC Inline Replacement Water Filter

    Omnipure ® CL-10RO-T/33 inline GAC carbon 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 available separately for 1/4" or 3/8" tube. 25 per case, priced and sold individually. Order a case and save even more.

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    $21.99 Special Price $11.99 As low as $9.49
  8. Omnipure CL-6RO-T/33 GAC Inline Replacement Water Filter-1000
    Omnipure ® CL-6RO-T/33 GAC Inline Water Filter
    Omnipure ® CL-6RO-T/33 GAC - 6" X 2" Carbon Inline Replacement Post Water Filter - GAC (granular activated carbon) Acid Washed Carbon - Should be changed at least every 12 months. 50 per case, sold individually. Order a case and save even more.

    Check Water Filter Connector Sizes

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    $17.99 Special Price $9.99 As low as $6.49
  9. WFO TFM-18 Reverse Osmosis Membrane - TFC 18 GPD
    WFO TFM-18 Reverse Osmosis Membrane - TFC 18 GPD

    WFO-TFM-18 Desal TFM-18 Compatible RO Membrane.  Replaces Desal Osmonics TFM-18 Reverse Osmosis Membrane.

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    $44.99 Special Price $33.98
  10. Pentek GAC-10 # 155109 GAC10 Taste & Odor Replacement Water Filter Cartridge
    Pentek GAC-10 # 155109 GAC10 Taste & Odor Water Filter Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek GAC-10 # 155109 GAC10 Taste & Odor Water Filter Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands Granular Activated Carbon Taste & Odor Water Filter. 9 3/4" long X 2 7/8" diameter. 12 per case, sold individually. Ametek # 155109 GAC Series cartridges effectively reduce unwanted tastes, odors and chlorine from your drinking water. They are designed to allow maximum contact between the water and carbon, ensuring maximum adsorption. The construction of the cartridge allows water to enter at one end and pass through the entire length of the cartridge, while an internal expansion pad minimizes channeling or bypass. Before the water exits the cartridge, a 20-micron post filter helps remove carbon fines and other suspended particles from the filtered water. Order a case and save even more.
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    $14.99 Special Price $9.99 As low as $7.99
  11. DESAL TFM-24 RO Reverse Osmosis Membrane #1220189 GE Osmonics Pentair - 1000
    Desal ® TFM-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. WE RECOMMEND REPLACING THE TFM-24 WITH THE TFM-36 AND MATCHING FLOW RESTRICTOR.

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    $89.99 Special Price $56.99 As low as $39.99
  12. 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
  13. 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
  14. 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
  15. 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
  16. PREVIOUS VERSION: Automatic Shut-Off Valve for the Reverse Osmosis RO System-ASP ASV-1000
    Automatic Shut Off Valve for reverse osmosis system - ASO ASV
    Auto Shut Off RO 1 - Automatic shutoff valve for reverse osmosis systems. ASO ASV Easy to use 1/4" OD Tube Jaco connectors included. - The "in & out" markings are on the top of the valve. The top side of the valve is the high pressure side and the bottom side is the low pressure side. The high pressure from the filter housings goes to the "in" on the top of the valve. Then the high pressure "out" goes to the membrane housing "in". The membrane housing low pressure "out" connects to the "in" on the bottom side of the valve. The "out" on the bottom goes to the tank. The valve automatically shuts off production when the tank pressure reaches approximately 65% of the incoming line pressure.
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    $28.99 Special Price $19.99 As low as $15.99
  17. 4 Stage Reverse Osmosis RO Pure Water System - Free Shipping *
    4 Stage Reverse Osmosis RO Pure Water System - Free Shipping *
    4 Stage Reverse Osmosis RO Pure Water System With Auto Shut Off Valve - 50 Gallon Per Day Filmtec TFC Reverse Osmosis Membrane (Higher capacity and faster recovery time) 50 GPD FILMTEC TFC Reverse Osmosis Membrane, KX Carbon Block & Osmonics Sediment Pre Filter, Omnipure GAC Post Filter. Uses Standard Size Replacement Filters. Includes New 4 Gallon Storage Tank (14 " high X 11 " diameter) , Long Reach CA Lead Safe Faucet & Installation Kit. System measures: 17" High X 14" Wide X 6" Deep
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    $279.99 Special Price $189.99 As low as $159.99
  18. 5 Stage Reverse Osmosis RO Pure Water System - Free Shipping *
    5 Stage Reverse Osmosis RO Pure Water System - Free Shipping *
    5 Stage Reverse Osmosis RO Pure Water System With Auto Shut Off Valve - 50 Gallon Per Day Filmtec TFC Reverse Osmosis Membrane (Higher capacity and faster recovery time) 50 GPD FILMTEC TFC Reverse Osmosis Membrane, KX Carbon Block & Osmonics Sediment Pre Filter, Omnipure GAC Post Filter. Uses Standard Size Replacement Filters Includes New 4 Gallon Storage Tank (14" high X 11"diameter) , Long Reach CA Lead Safe Faucet & Installation Kit. System measures: 17" High X 17" Wide X 6" Deep
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    $329.99 Special Price $219.99 As low as $195.99
  19. 5 Stage With Pump Reverse Osmosis RO Pure Drinking Water System
    5 Stage With Pump Reverse Osmosis RO Pure Drinking Water System
    5 Stage Reverse Osmosis RO Pure Water System With Auto Shut Off Valve - 50 Gallon Per Day Filmtec TFC Reverse Osmosis Membrane (Higher capacity and faster recovery time) 50 GPD FILMTEC TFC Reverse Osmosis Membrane, KX Carbon Block & Osmonics Sediment Pre Filter, Omnipure GAC Post Filter. Uses Standard Size Replacement Filters Includes New 4 Gallon Storage Tank (14" high X 11"diameter) , Long Reach CA Lead Safe Faucet & Installation Kit. System measures: 17" High X 17" Wide X 6" Deep
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    $399.99 Special Price $299.99 As low as $269.99
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.