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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RO/Conn Water Filters ®

RO/Conn Water Filters ®

RO/Conn ® Reverse Osmosis System Replacement Water Filters And Reverse Osmosis RO Membranes

  1. Pro Products Sani System Sanitizer
    Pro Products Sani System Sanitizer
    Pro Products Sani System Sanitizer. 0.25 or 0.5 fl. oz. concentrate. 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. 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. Sani-System is now NSF certified! This is the best sanitizing solution available anywhere! Stock up and save. Learn More
    $7.99 Special Price $4.99 As low as $2.49
  2. 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
  3. 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
  4. 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

    Learn More
    $5.99 Special Price $3.99 As low as $1.79
  5. Omnipure Water Filter Head Replacement #NVH1/4 (#VH1/4)
    Omnipure Water Filter Head Replacement #NVH1/4 (#VH1/4)
    Omnipure Water Filter Head Replacement. Non Valve and Valve In Head. 1/4" FNPT ports for easy installation of fittings. #NVH1/4 (#VH1/4) Add Bracket #Q-BRACKET for best installation. Learn More
    $24.99 Special Price $11.99 As low as $10.39
  6. Omnipure Q5605 5 Micron Sediment Replacement Water Pre-Filter- 1000
    Omnipure ® Q5605 5 Micron Sediment Water Prefilter
    Omnipure ® Q5605 5 Micron Sediment Water Prefilter "Q" Style Self Contained - "Q" Series Quick Connect. Learn More
    $24.99 Special Price $16.99 As low as $12.99
  7. Omnipure Q5615 - carbon 1 micron replacement prefilter or post water filter- 1000
    Omnipure ® Q5615 carbon 1 micron replacement prefilter or post water filter
    Omnipure ® Q5615 Carbon Block Replacement Prefilter and Post Water Filter. 1 Micron with lead removal. Upgrade To Carbon Block From Standard GAC Carbon. No "Carbon Fines" Released. Learn More
    $39.99 Special Price $29.99 As low as $25.99
  8. Omnipure Q5620 1 Micron Carbon Block Replacement Pre-Filter and Post-Water Filter- 1000
    Omnipure ® Q5620 1 Micron Carbon Block Replacement Prefilter and Post Water Filter
    Omnipure ® Q5620 1 Micron Carbon Block Replacement Prefilter and Post Water Filter. Learn More
    $35.99 Special Price $24.99 As low as $19.99
  9. Omnipure Q5621- Carbon Replacement Pre-filter and Post-Water Filter- 1000
    Omnipure ® Q5621 Carbon Pre/Post Water Filter
    Omnipure ® Q5621 Carbon Block Pre/Post Water Filter. 10 Micron. Upgrade To Carbon Block From Standard GAC Carbon. No "Carbon Fines" Released. Learn More
    $36.99 Special Price $25.99 As low as $21.99
  10. Omnipure Q5633- Carbon Replacement Prefilter and Post Water Filter-1000
    Omnipure ® Q5633 Carbon Pre/Post Water Filter
    Omnipure ® Q5633 Carbon Replacement Prefilter and Post Water Filter. "Q" Series Quick Connect Sanitary Change. Granular Activated Carbon - T33 GAC Filtration. Learn More
    $27.99 Special Price $18.99 As low as $14.99
  11. Omnipure Q5686 Carbon Phosphate Replacement Water Filter For Scale Control-1000
    Omnipure ® Q5686 Carbon Phosphate Replacement Water Filter For Scale Control
    Omnipure ® Q5686 Carbon Phosphate Replacement Water Filter For Scale Control. Omnipure "Q" Series Quick Connect For Sanitary Filter Changes. GAC Granular Activated Carbon With Phosphate. Learn More
    $32.99 Special Price $22.99 As low as $18.99
  12. Omnipure ® TQ56-15FC 15 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control
    Omnipure ® TQ56-15FC 15 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control
    Omnipure ® TQ56-15FC 15 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control. Omnipure Q Series Sanitary Quick Change Replacement RO Reverse Osmosis Membrane. Learn More
    $89.99 Special Price $69.99 As low as $58.99
  13. Omnipure ® TQ56-36FC 36 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control
    Omnipure ® TQ56-36FC 36 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control
    Omnipure ® TQ56-36FC 36 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control. Omnipure Q Series Sanitary Quick Change Replacement RO Reverse Osmosis Membrane. Learn More
    $115.00 Special Price $84.99 As low as $73.99
  14. Omnipure ® TQ56-50FC 50 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control
    Omnipure ® TQ56-50FC 50 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control
    Omnipure ® TQ56-50FC 50 GPD TFC RO Reverse Osmosis Membrane With Built-In Flow Control. Omnipure Q Series Sanitary Quick Change Replacement RO Reverse Osmosis Membrane. Learn More
    $125.00 Special Price $89.99 As low as $77.99
  15. 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
  16. 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

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.


* RO/Conn ® is the registered trademark of RO/Conn, the manufacturer of RO/Conn ® brand water treatment equipment.  The replacement filters and membranes listed above are not manufactured or endorsed by RO/Conn.  Rather, these filters and membranes are manufactured by other companies.  While these filters and membranes are compatible for use in RO/Conn ® AQPC-35 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 RO/Conn ® equipment.