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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Nugen RO-3-25 3 Stage TFC-24 Reverse Osmosis RO Pure Drinking Water System Help

Nugen RO-3-25 3 Stage TFC-24 Reverse Osmosis RO Pure Drinking Water System Help

Nugen RO-3-25 3 Stage TFC-24 Reverse Osmosis RO Pure Drinking Water System Help

Nugen RO-3-25 replacement water filters, RO reverse osmosis membranes and maintenance parts to maintain your reverse osmosis system.

  1. 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 Learn More
    $12.99 Special Price $9.99 As low as $7.79
  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. Learn More
    $23.99 Special Price $15.99 As low as $11.99
  3. Flow_Restrictor-250-1000
    Flow Restrictor - Inline - 250 ml 1/4' quick connect fittings

    Flow Restrictor - capillary - 250 ml 1/4" quick connect fittings. 

    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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    $19.99
  4. Pentek SW-1A # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench
    Pentek SW-1A # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek SW-1 # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. SW-1 Water Filter Housing Wrench. Fits 4" Slim Line Housings. (Slim Line Housings Have A 3 1/2" diameter "O" Ring) Ametek # 150294 Only for use in loosening filter housings, never to tighten. Overtightening may cause damage to the O-rings and make re-opening VERY difficult. Hand tighten only. Fits most standard style RO systems. Replaces 150294. For really stubborn filter housings our technicians will use two wrenches together for maximum power where one wrench might break or not do the job. Our techs know the tricks. Order New O-rings And Be Sure To Lube Them With Dow 111 Silicone Sealant To Prevent Leaks Learn More
    $9.99 Special Price $6.99 As low as $4.99
  5. 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
  6. 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
  7. Air Pressure Gauge for Reverse Osmosis Water Accumulator Tanks -1000
    Air pressure gauge for reverse osmosis water accumulator tanks
    Air pressure gauge for reverse osmosis water accumulator tanks - Specially calibrated for reverse osmosis system tanks. Scale from 1 to 20 PSI. Large scale reading over small PSI range allows optimum accuracy. Just like car tires lose air pressure, so does the bladder of your reverse osmosis water accumulator tank. Improper tank air pressure will cause your system to operate improperly. This is a must for all reverse osmosis system owners. Learn More
    $24.99 Special Price $17.99 As low as $12.99
  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
  9. 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
  10. Chiller Daddy CHL-750XL Under Sink Water Chiller
    Chiller Daddy CHL-750XL Under Sink Water Chiller

    Chiller Daddy ® CHL-750XL Under Sink Water Chiller -  NEW TANK IS 25% LARGER than our previous chillers.  Output Cold Tank Volume : 3 liter (0.8 gallon) Exterior cabinet is made of RUST FREE 304 SS Stainless Steel. Cold Water Container is made of SUS304 Stainless Steel. Inlets and outlets are 1/4" stainless steel 304. Includes a pair of quick connectors for a simple hook up. Output of Cold Water : 1.34 Gallons Per Hour (5 Liters 5L/H (<10C) Continuous Cold Water Output(cc/hr) 5,400. This is a high output, heavy duty undersink drinking water chiller. Great for use with a Reverse Osmosis System or drinking water filter system.

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    $499.99 Special Price $349.99 As low as $310.99
  11. Inline Water Shut Off Valve-1000
    Inline Water Shut Off Valve - Great For Refrigerators And Ice Machines
    Inline Water Shut Off Valve With 1/4" or 3/8" Quick Connect Fittings - Very easy to install and use. - Great for refrigerators, UV systems, chillers, hot pots, coffee machines, ice machines etc. Learn More
    $14.99 Special Price $9.99 As low as $6.99
  12. John Guest ® Tee Connector For water Systems - Quick Connectors
    John Guest ® Tee Connector For Water Systems - Quick Connectors
    John Guest ® Tee Connector - Quick Connectors - All equal size connections or one port different for adaption. The body is produced in acetal copolymer. 'O'Rings are nitrile rubber. The collet is produced in acetal copolymer with stainless steel teeth. PI0208S , PI0212S , PI301208S , PI301612S. Learn More
    $14.99 Special Price $9.99 As low as $7.99
  13. 3M  6-in-1 Water Test Kit -Simple to Use - DIY In Home Water Quality Test Kit
    3M 6-in-1 Water Test Kit -Simple to Use - DIY In Home Water Quality Test Kit
    6 in 1 Home Water Test Kit by 3M. Use this 3M DIY water quality test for convenient on-site testing. The 3M DIY water quality test kit provides quick analysis. Learn More
    $15.75 Special Price $12.99
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 replacement parts for your Nugen RO-3-25 Reverse Osmosis System such as TDS Testers For Reverse Osmosis Membranes, Replacement Tanks, O-ringsFaucets, Pumps, Fittings, UV Systems and more service parts for your reverse osmosis pure water filter system.   View maintenance and servicing tips for Nugen RO-3-25 drinking water filter system online at our Installation & Trouble Shooting Guide.

* Nugen RO-3-25 ® is the registered trademark of Nugen, the manufacturer of Nugen RO-3-25 brand drinking water filtration equipment.  The replacement water filters and reverse osmosis membranes listed above are not manufactured or endorsed by Nugen RO-3-25.  Rather, these replacement filters and RO membranes are manufactured by other companies.  While these filters and membranes are compatible for use in Nugen RO-3-25 reverse osmosis water filtration equipment, we make no representation as to whether using these water filters and RO membranes is consistent with the warranty and specifications applicable to Nugen RO-3-25 equipment.