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RainSoft  9590 & 9593 Reverse Osmosis System Water Filters

RainSoft 9590 & 9593 Reverse Osmosis System Water Filters

RainSoft ® 9590 & 9593 Ultrefiner Reverse Osmosis System Compatible Replacement Water Filters And Reverse Osmosis RO Membranes.

This system originally came with a CTA RO reverse osmosis membrane.  As CTA membranes are rarely manufactured anymore, we suggest updating your system to use the TFC membrane shown below.  TFC membranes have better performance and last longer.  You will need to update the Flow Restrictor to match the new membrane.   Also the sediment pre filter will need to be replaced by a sediment/carbon combination pre filter as shown below.  

  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. Omnipure CL-6RO-T/33 GAC Inline Replacement Water Filter-1000
    Omnipure ® CL-6RO-T/33 GAC Inline Water Filter
    Omnipure ® CL-6RO-T/33 GAC - 6" X 2" Carbon Inline Replacement Post Water Filter - GAC (granular activated carbon) Acid Washed Carbon - Should be changed at least every 12 months. 50 per case, sold individually. Order a case and save even more.

    Check Water Filter Connector Sizes

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    $17.99 Special Price $9.99 As low as $6.49
  3. Flow_Restrictor-500  Flow Restrictor - capillary - 500 ml  1/4' quick connect fit-1000
    Flow Restrictor - Inline - 500 ml 1/4' quick connect fit...

    Flow Restrictor - capillary - 500 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. 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
  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. C Shaped Open End Universal Style Water Filter Sump Spanner Wrench
    C Shaped Open End Universal Style Water Filter Sump Spanner Wrench
    C Shaped Open End Filter Wrench - Universal "C" style wrench for all standard size and Slimline water filter housings. 3 5/8" opening. 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. 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. Learn More
    $9.99 Special Price $6.99 As low as $2.99
  7. PENTEK- #151121- Slim-Line Water Filter Housing Replacement - 1000
    Pentek # 151121 O-Ring For Slim Line Water Filter Housing Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek # 151121 O-Ring For Slim Line Water Filter Housing Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. O-Ring For Slim Line Water Filter Housing. Buna-N FDA Grade. (Slim Line Housings Use A 3 1/2" diameter "O" Ring) Ametek # 151121 Same as Culligan OR-38 O-ring. Learn More
    $5.69 Special Price $4.99 As low as $3.00
  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. 4 Gallon Reverse Osmosis Water Tank Replacement - GGN-Tank-4-Pro 3.2
    4 Gallon Reverse Osmosis Water Tank Replacement - GGN-Tank-4-Pro 3.2

    4 Gallon Reverse Osmosis Tank GGN-Tank-4 Pro 3.2. This is the perfect replacement tank for most RO reverse osmosis systems.   Stainless Steel valve connector.  Perfect replacement for all home RO reverse osmosis drinking water systems.  

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    $79.99 Special Price $49.99
  11.  Inversion Tank Stand Reverse Osmosis System
    Inversion Tank Stand Reverse Osmosis System

    Inversion Stand for Water Tank on  Reverse Osmosis Systems.  Flip the tank over and remove the weight of the water from the bladder.  Pressure and storage capacity are unchanged.  Extends the life of your reverse osmosis water tank.

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    $27.99 Special Price $17.99
  12. 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
  13. 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
  14. 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

Easy TDS Membrane Performance 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.