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RainSoft 9591 Reverse Osmosis System Water Filters

RainSoft  9591 Reverse Osmosis System Water Filters
  1. 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 Replacement
    KX Matrikx ® 10/2 Carbon Block Water Filter # 10-250-190-975 Compatible Replacement. If you order the KX 10/2 you will receive the GGN 10/2 as the new replacement as the KX 10/2 has been discontinued by KX Industries. 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. Learn More
    $17.99 Special Price $9.99 As low as $6.99
  2. Omnipure CL-6RO-T/33 GAC Inline Replacement Water Filter-1000
    Omnipure ® CL-6RO-T/33 GAC Inline Replacement Water Filter
    Omnipure ® CL-6RO-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 availble seperately for 1/4" or 3/8" tube. 50 per case, priced and sold individually. Order a case and save even more. Learn More
    $17.99 Special Price $9.99 As low as $6.49
  3. RainSoft Ultrefiner TFC-RS9-12-Compatible Reverse Osmosis RO Membrane 9565 17375-1000
    RainSoft ® Ultrefiner TFC-RS9-12 Compatible Reverse Osmosis RO Membrane 9565 17375
    RainSoft ® Ultrefiner TFC-RS9-12 Compatible Reverse Osmosis RO Membrane 9565 17375. TFC 12 Gallon Per Day Membrane - Ref # 13016, 17375 for 9565 and others. (fits 9591, 9594, 9565 & others) Learn More
    $69.99 Special Price $45.99 As low as $29.99
  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? Learn More
    $5.99 Special Price $3.99 As low as $1.79
  5. 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.. Learn More
    $7.99 Special Price $4.99 As low as $2.49
  6. GGN-Faucet-AG-P-Chrome Air Gap Faucet-Long Reach-1000
    Chrome Air Gap Faucet - Long Reach GGN-FAUCET-AG-P

    Chrome Air Gap Faucet - Long Reach GGN-FAUCET-AG-P.  The perfect replacement faucet for under sink reverse osmosis systems.

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    $39.99 Special Price $29.99
  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 Learn More
    $49.99 Special Price $37.99 As low as $17.99
  9. TDS Water Meter Dual Mode Readings - DM2 HM Digital Professional Grade
    TDS Water Meter Dual Mode Readings - DM2 HM Digital Professional Grade - Easily Installs Inline - Very Simple To Use
    TDS Meter Dual Mode Readings - Professional Grade - Easily Installs Inline - Very Simple To Use. Measure the tap water coming in vs. the purified water going out of your system at any time. Use the meter to determine when the filters need to be changed. Highly efficient and accurate due to its advanced microprocessor technology. Displays TDS levels of the Feed Water and Product Water with in & out electrode probes. Auto-Off function conserves battery power. The unit shuts off automatically after 20 seconds. Dual Range - Measures from 0-999 ppm, with a resolution of 1 ppm. Learn More
    $69.99 Special Price $49.99 As low as $29.99
  10. TDS Meter Inline Water Tester DM1 - HM Digital Dual Mode Reading
    TDS Meter Inline Water Tester DM1 - HM Digital Dual Mode Reading - Easily Installs Inline - Very Simple To Use
    TDS Water Meter - HM Digital DM1 - 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. 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. Dual Range 0-9990 ppm. Always know if your RO membrane is performing correctly! Learn More
    $49.99 Special Price $39.99 As low as $19.99
  11. 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
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.

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