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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Reverse Osmosis Systems

Reverse Osmosis Systems

RO Reverse Osmosis Systems Receive Free Shipping Within Continental U.S.

Optional Faucets

UV Disinfection

Inline TDS Meters / Testers

  1. Countertop 50 GPD RO Reverse Osmosis Water Purification System - Free Shipping
    Countertop 50 GPD RO Reverse Osmosis Water Purification System - Free Shipping
    Free Shipping. Easy To Install. Countertop design. 50 GPD high capacity, fast recovery system. Attaches to existing kitchen faucets. No need to alter the plumbing. Great for apartment dwellers. Portable, take it from one faucet to another. 50 GPD TFC membrane. Easy to find and install Omnipure replacement filters. K2505, K2533 and K2540. Uses standard Filmtec TW30-1812-50 RO Reverse Osmosis membrane. This countertop system uses top quality, easy to find replacement water filters and RO membrane. Easy to replace filters with Quick Connectors. RO System #RC540T50 14 3/" Tall x 10 3/4" Wide x 10" Deep (plus 2 1/2" spigot) Absolute top quality countertop system. Learn More
    $199.95 Special Price $129.95 As low as $110.00
  2. 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 Learn More
    $269.99 Special Price $179.99 As low as $129.99
  3. 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 Learn More
    $299.99 Special Price $199.99 As low as $159.99
  4. 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 Learn More
    $399.99 Special Price $289.99 As low as $229.99
  5.  GGN-SSRO-215
    Stainless Steel Tankless Reverse Osmosis Drinking Water RO System
    Use in Place of the GE Merlin Tankless RO Reverse Osmosis System. This Commercial Grade Construction Using Food Grade Stainless Steel is designed for commercial and/or Residential Use. Its Tankless Operation or Stainless Steel 4.4 Gallon Tank for Highest Flow Rates and High Demand usage with a 400 GPD Gallons Per Day High Production Capacity. Learn More
    $299.99 Special Price $159.50
  6. PuroTwist 4 Stage 50 GPD RO Reverse Osmosis TFC Membrane Quick Change Water Filtration Retro Fit System
    PuroTwist 4 Stage 50 GPD RO Reverse Osmosis TFC Membrane Quick Change Water Filtration Retro Fit System
    PuroTwist 4 Stage 50 GPD TFC Quick Change Water Filtration Retro Fit System. Quick change head with 50 GPD membrane, Q5605 sediment prefilter, Q-5633 GAC carbon prefilter and post filter No tank, faucet or installation kit. Uses John Guest quick connectors that are very easy to install. Works in place of the ® DuPure or ® Rayne "-60" Pure Blue - ® Omnipure -60 "Q" Series systems. Learn More
    $279.99 Special Price $189.99 As low as $154.99
  7. PuroTwist 3 Stage 50 GPD RO Reverse Osmosis TFC Membrane Quick Change Water Filtration Retro Fit System
    PuroTwist 3 Stage 50 GPD RO Reverse Osmosis TFC Membrane Quick Change Water Filtration Retro Fit System
    PuROTwist 3 Stage 50 GPD RO Reverse Osmosis TFC Membrane Quick Change Water Filtration Retro Fit System. PT3000T50-SS-RK Quick change head with 50 GPD membrane, Q5621 carbon block prefilter and Q5633 GAC post filter. No tank, faucet or installation kit. Uses John Guest quick connectors that are very easy to install. Works in place of the ® DuPure or ® Rayne "-60" Pure Blue - ® Omnipure -60 "Q" Series systems shown in the photo. Learn More
    $249.99 Special Price $179.99 As low as $144.99
  8. PuroTwist ® 4000 Reverse Osmosis RO System - Free Shipping *
    PuroTwist ® 4000 Reverse Osmosis RO System - Free Shipping *
    PuroTwist ® 4000 Reverse Osmosis System - 4 Stage RO Reverse Osmosis Pure Water Drinking System. 50 Gallon Per Day TFC Reverse Osmosis Membrane (Valve in head for easy filter changes) 50 GPD TFC Reverse Osmosis Membrane, Uses Easy Change Replacement Filters. Includes Storage Tank, Long Reach California Prop. 65 lead safe faucet, Filters & Installation Kit.. Simple system to maintain. PT4000-T50-SSNA. Dimensions: Filter and Head 19" high, 12" wide, 4 1/2" deep. Tank 14" high, 10" diameter. Learn More
    $369.99 Special Price $279.99 As low as $239.99
  9. PuroTwist ® 3000 Reverse Osmosis RO System - Free Shipping *
    PuroTwist ® 3000 Reverse Osmosis RO System - Free Shipping *
    PuroTwist ® 3000 Reverse Osmosis System - 3 Stage RO Reverse Osmosis Pure Water Drinking System - 18 Gallon Per Day CTA Reverse Osmosis Membrane (Valve in head for easy filter changes) (1) 5 Micron Sediment Pre-Filter (1) 18 GPD CTA Reverse Osmosis Membrane (1) Carbon Polishing Post Filter Uses Easy Change Replacement Filters. California Prop. 65 lead safe faucet. Includes Filters & Installation Kit. Simple system to maintain. Learn More
    $299.99 Special Price $229.99 As low as $196.99
  10. Hydrotech ® 4VTFC75G Reverse Osmosis System RO # 12302003
    Hydrotech (Aqua Flo) ® 4VTFC75G Reverse Osmosis System RO # 12302003 - FREE SHIPPING
    Hydrotech (Aqua Flo) ® 4VTFC75G Reverse Osmosis Drinking Water System RO. 75 Gallon Per Day GPD. TFC Thin Film Composite membrane, sediment pre filter, carbon pre filter, carbon post filter, auto shut off valve, California Prop. 65 lead safe 3/8" flow air gap faucet, and your choice of metal or polypropylene tank. System is 15" wide X 15" high X 3" deep. Plastic tank is 14 1/4" high X 10" diameter. Metal tank is 15" high X 11" diameter. # 12302003. Learn More
    $399.99 Special Price $229.99 As low as $189.99
  11. Aqua Flo RO75 Reverse Osmosis System #20010073
    Aqua Flo RO75 Reverse Osmosis System #20010073
    Aqua Flo RO75 Reverse Osmosis System. 5 stage RO reverse osmosis system. Comes with tank, faucet, tubes, filters and membrane. Everything for a normal installation. Uses standard style and size replacement filters. Learn More
    $229.99 Special Price $169.99 As low as $159.99
  12. Pentair-GRO-475B
    Pentair-GRO-475B
    Pentair GRO-475B 4 Stage RO System 161111 Learn More
    $399.99
  13. Aqua Flo RO75BP Reverse Osmosis System - 5 Stage With Booster Pump #20010074
    Aqua Flo RO75BP Reverse Osmosis System - 5 Stage With Booster Pump #20010074
    Aqua Flo RO75BP Reverse Osmosis System. 5 stage RO reverse osmosis system. Comes with tank, faucet, tubes, filters and membrane. Everything for a normal installation. Uses standard style and size replacement filters. Learn More
    $299.99 Special Price $239.00 As low as $215.00
  14. Pentair GRO-75EN 75 GPD 4 Stage RO System.
    Pentair GRO-75EN 75 GPD 4 Stage RO System.
    Pentair GRO-75EN 75 GPD 4 Stage RO System. Learn More
    $299.99
  15. 3MRO301 3 Stage Reverse Osmosis System
    3MRO301 3 Stage Reverse Osmosis System
    3MRO301 Reverse Osmosis System #04-04506 This Reverse Osmosis (RO) system with advanced three stage filtration process includes a Sediment/Carbon Pre Filter, a Carbon Block Filtration Post Filter, and a Reverse Osmosis. Included in the package: RO system with 3 filter cartridges, faucet, tank, tubing, fittings, installation manuel and performance data sheet Learn More
    $489.00 Special Price $399.99 As low as $379.00
  16. 3MRO401 4 Stage Reverse Osmosis System
    3MRO401 4 Stage Reverse Osmosis System
    The 3MRO401 replaces the SQC4 to help provide cleaner, better tasting water through reverse osmosis The 3M reverse osmosis filtration system helps provide cleaner, better tasting water through reverse osmosis filtration. It offers multi-stage filtration, incorporating separate sediment and chlorine taste; odor filters for excellent membrane module protection, a sanitary, encapsulated reverse osmosis membrane and carbon block post-filter for superior flow from a dedicated faucet. Learn More
    $983.46 Special Price $549.95 As low as $499.00
  17. 3MRO501 Reverse Osmosis System With Pump
    3MRO501 Reverse Osmosis System With Pump
    3M RO 501 Reverse Osmosis System Our 3MRO501 systems install under the kitchen sink and deliver cleaner, clearer, better tasting drinking water through a dedicated drinking water faucet. These systems provide water filtration on demand for drinking water, coffee, tea, baby formula, etc. and for cooking purposes as well. Our universal system design allows for use on both chlorinated (municipal) and non-chlorinated (well water) systems. Learn More
    $2,265.14 Special Price $998.00 As low as $959.00
  18. Aqua-Pure ® AP-RO5500 Reverse Osmosis System by 3M Purification - Free Shipping *
    Aqua-Pure ® AP-RO5500 Reverse Osmosis System by 3M Purification - Free Shipping *
    DISCONTINUED - WE STILL HAVE REPLACEMENT FILTERS, RO MEMBRANES AND PARTS FOR THIS SYSTEM. Aqua-Pure ® AP-RO5500 Reverse Osmosis System by 3M Purification # 55982-01- Undersink Reverse Osmosis System. 12 - 18 GPD TFC membrane, automatic shut-off valve. Compact design. Includes faucet and AP5527 cartridges. - aka AquaPure or Aqua Pure. Learn More
    $599.99 Special Price $399.99 As low as $379.99
  19. Pentek RO-2550 RO 50 GPD Reverse Osmosis System
    Pentek RO-2550 RO 50 GPD 4 Stage Reverse Osmosis RO System
    Pentek RO-2550 4 Stage Reverse Osmosis Pure Water System With Auto Shut Off Valve - 50 Gallon Per Day TFC Reverse Osmosis Membrane (Higher capacity and faster recovery time). Tested and Certified by NSF International against NSF/ANSI Standard 58 for the reduction of Total Dissolved Solids, Fluoride, Turbidity, Lead, Selenium, and Copper. Uses Standard Size Replacement Filters. Includes New 3.2 Gallon Storage Tank (14" high X 9 1/2" diameter) , Long Reach Air Gap Faucet & Installation Kit. System measures: 14" High X 15 1/2" Wide X 5 1/4" Deep Learn More
    $259.99 Special Price $139.99
  20. OMNIFILTER RO2050 Reverse Osmosis System
    OMNIFILTER RO2050 Reverse Osmosis System

    OMNIFILTER RO2050 ® Reverse Osmosis System

    • Deluxe 4-stage reverse osmosis water filter
    • Ultimate water filtration - bottle water quality
    • Use for chlorinated and non-chlorinated water
    • Reduces sediment & rust particles, chlorine taste & odor plus chemicals, cysts, lead & TDS
    • Includes 5-micron prefilter, membrane, carbon filter, GAC post filter, 3-gal. pressure tank, air gap faucet, installation hardware & wrench
    Learn More
    $249.99 Special Price $189.95
  21. Water Factory ® SQC-3 HF Reverse Osmosis System 04-045 by 3M Purification - Free Shipping *
    Water Factory ® SQC-3 HF Reverse Osmosis System 04-045 by 3M Purification - Free Shipping *
    Water Factory ® SQC-3 HF Reverse Osmosis System Includes Tank 04-045 by 3M Purification. The Water Factory System's SQC 3 HF under-the-counter reverse osmosis unit is a three (3) stage system designed for use on either chlorinated or non-chlorinated water supplies. The sanitary quick-change cartridges enable easy changes with no mess. The SQC 3 HF Model can produce up to 20 gallons of drinking water a day and can be installed to feed an ice-maker within your refrigerator. The minimum water pressure requirement of the SQC 3 HF Models is 50 psi. Uses (#1) 47-55706G2 Sediment/Carbon Prefilter, (#2) 66-4706G2 TFC HF Reverse Osmosis Membrane and (#3) 47-55710G2 Block Carbon Postfilter. Learn More
    $559.99 Special Price $469.99 As low as $439.99
  22. Everpure ® ROM III Reverse Osmosis System # 9273-76K
    Everpure ® ROM III Reverse Osmosis System # 9273-76K
    Everpure ® ROM III Reverse Osmosis System # 9273-76K • Commercial-quality Reverse Osmosis drinking water system for your home. • Reduces TDS. • Capacity: 500 gal • Flow Rate: 14.4 gal/day • Certifications: NSF 58. Includes tank, faucet and installation kit. Learn More
    $799.99 Special Price $599.99 As low as $559.99
  23. Everpure ® ROM II DWS Reverse Osmosis System # 9273-75K
    Everpure ® ROM II DWS Reverse Osmosis System # 9273-75K
    Everpure ® ROM II DWS Reverse Osmosis System # 9273-75K Same as ROM III except does not contain VOC "C" cartridge • Commercial-quality Reverse Osmosis drinking water system for your home. • Reduces TDS. • Capacity: 500 gal • Flow Rate: 14.4 gal/day • Certifications: NSF 58. Includes tank, faucet and installation kit. Learn More
    $699.99 Special Price $524.99 As low as $484.99

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.