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 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
  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. 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

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.