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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Sierra Springs Reverse Osmosis Water Filters

Sierra Springs Reverse Osmosis Water Filters

Sierra Springs Reverse Osmosis System RO Replacement Water Filters, RO Reverse Osmosis Membranes, Faucets, Water Accumulator Tanks and DIY Service Parts.

Sediment filters need changed twice as often as carbon filters so order 2 for every carbon filter pair change, normally one year.  This system takes 2 carbon filters per filter change.  So order 2 sediment filters (change one every 6 months), 2 carbon filters (change both every 12 months) and the 75 gallons per day reverse osmosis membrane (change as needed per TDS meter readings).  Be sure to order sanitizer to disinfect the system, tank, faucet and lines as you perform the filter change.


Hydrotech 1240 / 1230 Series Reverse Osmosis System Owner's Manual

We have been an authorized Hydrotech dealer dating back before we became one of the first online water filter stores in 1999.  Our techs have been servicing Hydrotech and Aquaflo reverse osmosis systems since 1989.  We know Hydrotech.


  1. Hydrotech ® 4VTFC75G Reverse Osmosis System RO # 12302003
    Hydrotech (Aqua Flo) ® 4VTFC75G Reverse Osmosis System RO #1240203
    Hydrotech (Aqua Flo) ® 4VTFC75G Reverse Osmosis Drinking Water System RO. 75 Gallon Per Day GPD. TFC Thin Film Composite membrane, sediment pre filter, carbon pre filter, carbon post filter, auto shut off valve, California Prop. 65 lead safe 3/8" flow air gap faucet, and your choice of metal or polypropylene tank. System is 15" wide X 15" high X 3" deep. Plastic tank is 20" high X 8" diameter. Metal tank is 15" high X 11" diameter. # 12302003.
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    $399.99 Special Price $249.99 As low as $239.99
  2. Hydrotech ® S-FS-02 & Aquafier Sediment Replacement Water Filter # 41400008
    Hydrotech ® S-FS-02 Sediment Replacement Water Filter For 1230/1240 SERIES #41400008

    Hydrotech ® S-FS-02 Sediment Replacement Water Filter Cartridge For Series HT & HTF 1230/1240 Reverse Osmosis RO Systems.  #41400008. String Wound Depth Gradient Sediement Pre Filter. (Black End Caps)  

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    $17.99 Special Price $9.99 As low as $6.99
  3. Hydrotech Dual Purpose Sediment / GAC Carbon Replacement Water Pre Filter 41400076
    Hydrotech Dual Purpose Sediment / GAC Carbon Replacement Water Pre Filter 41400076

    The Hydrotech 41400076 Carbon/Sediment Cartridge is the genuine dual purpose filter.  The 41400076 cartridge filters sediment, dirt and rust particulate down to 5 microns. The carbon block media reduces bad tastes and odor in addition to chlorine which can damage your RO membrane.

    The Hydrotech 41400076 Carbon/Sediment Cartride is used on a wide variety of Hydrotech 3 vessel Reverse Osmosis systems, including the 12401, HT102, HT103, HT12301 Systems. 

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    $38.90 Special Price $29.99
  4. Hydrotech ® S-FS-19 & Aquafier Carbon Block Replacement Water Filter # 41400009
    Hydrotech ® S-FS-19 & Aquafier Carbon Block Water Filter # 41400009
    Hydrotech ® S-FS-19 & Aquafier Carbon Block Water Filter. CTO 10 Micron (Blue End Caps) # 41400009 For HT & HTF Series Reverse Osmosis RO Systems. a.k.a. #41400075
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    $21.99 Special Price $12.99 As low as $9.99
  5. HYDROTECH- S-FS-09 25 GPD TFC RO Reverse Osmosis Membrane #41400005, #33001068 - 1000
    Hydrotech ® S-FS-09 25 GPD TFC RO Membrane #41400005, #33001068
    Hydrotech ® S-FS-09 25 GPD TFC Reverse Osmosis RO Membrane. #41400005 (Green/Black Band), #33001068 (Yellow/Black Band or Blue/Black Band) For HT & HTF Series Systems.
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    $99.99 Special Price $76.99 As low as $62.99
  6. HYDROTECH S-FS-17 - 9 GPD TFC RO Reverse Osmosis Membrane #4140003, 33001071- 1000
    Hydrotech ® S-FS-17 9 GPD TFC RO Reverse Osmosis Membrane # 41400003, 33001071 (#41400004)
    Hydrotech ® S-FS-17 9 GPD Reverse Osmsosis RO Membrane Has Been Discontinued And Is No Longer Available. If You Order The S-SF-17 9 GPD TFC Membrane You Will Receive The Hydrotech S-FS-07 15 GPD TFC Membrane #41400004. #41400003 (Green/Red Band) #33001071 (Yellow/Red Band or Blue/Red Band) For HT & HTF Series Reverse Osmosis RO Systems.
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    $99.99 Special Price $69.99 As low as $54.99
  7. Hydrotech S-FS-07 - 15 GPD TFC RO Membrane #4140000 - 1000
    Hydrotech ® S-FS-07 15 GPD TFC RO Membrane # 41400004
    Hydrotech ® S-FS-07 15 GPD TFC Reverse Osmosis RO Membrane. (Green/Yellow Band, Yellow/Green Band or Blue/Yellow Band) # 41400004 For HT & HTF Series Systems.
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    $99.99 Special Price $69.99 As low as $54.99
  8. HYDROTECH- S-FS-11 - GPD TFC RO Reverse Osmosis Membrane 41400006- 1000
    Hydrotech ® S-FS-11 35 GPD TFC RO Membrane # 41400006
    Hydrotech ® S-FS-11 35 GPD TFC Reverse Osmosis RO Membrane. (Green/Purple Band or Yellow/Purple and Green Bands) # 41400006 For HT & HTF Series Systems.
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    $99.99 Special Price $79.99 As low as $64.99
  9. Hydrotech S-FS-20 45 GPD TFC RO Reverse Osmosis Membrane #41400007 - 1000
    Hydrotech ® S-FS-20 45 GPD TFC RO Reverse Osmosis Membrane # 41400007/33001033
    Hydrotech ® S-FS-20 45 GPD TFC Reverse Osmosis RO Membrane. (Green/Orange Band) # 41400007 For HT & HTF Series Reverse Osmosis RO Systems. The #41400007 has been replaced with the 50 GPD #33001033. If you order the #41400007 you will receive the #33001033.
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    $139.99 Special Price $99.99 As low as $79.99
  10. HYDROTECH 50 GPD TFC RO Reverse Osmosis Membrane #33001033- 1000
    Hydrotech ® 50 GPD TFC RO Membrane #33001033
    Hydrotech ® 3300103 50 GPD TFC Reverse Osmosis RO Membrane. (Yellow/White Band or Blue/White Band) # 33001033 For HT & HTF Series Reverse Osmosis RO Systems.
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    $139.99 Special Price $99.99 As low as $79.99
  11. Hydrotech ® HT-HTF & Aquafier Filter Housing Sump # 20500023
    Hydrotech ® HT-HTF & Aquafier Filter Housing Sump # 20500023
    Hydrotech ® HT-HTF & Aquafier Replacement Water Filter Housing Sump. # C-HT-19 # 20500023 For HT-HTF and Aquafier Series Reverse Osmosis RO Systems.
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    $39.99 Special Price $27.99 As low as $24.99
  12. Hydrotech ® HT-HTF Water Filter Wrench # 21401003
    Hydrotech ® HT-HTF Water Filter Wrench # 21401003
    Hydrotech ® E-VW-01 Filter Housing Spanner Wrench for Old Style 1230 HT-HTF Series Reverse Osmosis RO Systems. Also for the Aquifier series systems. For housing removal only. # 21401003. FOR THE NEW STYLE 1240 HT-HTF SEREIS REVERSE OSMOSIS SYSTEMS SELECT THE LARGE WRENCH (#21401240) IN THE DROP DOWN BOX.
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    $12.99 Special Price $7.99 As low as $6.49
  13. Hydrotech ® 34201026, Hydrofiner & Aquafier O-ring for water filter housing sump
    Hydrotech ® 34201026 & Aquafier O-ring for filter housing
    Hydrotech ® 34201026 & Aquafier O-ring for filter housing. Fits Hydrotech, Aquafier and Hydrofiner systems. 2 1/2" diameter
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    $8.99 Special Price $4.99 As low as $3.39
  14. 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
  15. 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..
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    $7.99 Special Price $4.99 As low as $2.49
  16. 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 drinking water systems.  Works as air gap or non air gap.  Quick release when drawing a glass of water or lock it on to fill a pitcher or cooking pot.   This is a top selling replacement faucet for most reverse osmosis systems.

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    $39.99 Special Price $29.99
  17. Puroflo FLR-868 faucet
    Puroflo FLR-868 Chrome Non-Air Gap Faucet
    Puroflo FLR-868 Long Reach Chrome Non-Air Gap Premium Faucet is NSF Certified. Smooth operating ceramic disk design with 12" High Reach Neck Design. California Prop. 65 and AB1953 compliant. Low Lead Level
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    $41.99 Special Price $29.99
  18. Stainless Steel Designer Faucet for RO Reverse Osmosis & Drinking Water Filtration Systems
    Stainless Steel Designer Faucet for RO Reverse Osmosis & Drinking Water Filtration Systems
    Stainless Steel Designer Faucet for Drinking Water Systems. Beautiful designer faucet for beautiful kitchens. Air Gap / Non Air Gap design, single or three tube connection. Made of high quality 304 stainless steel incorporating a smooth operating ceramic disk element for extended reliability and quality. Great replacement upgrade for RO Reverse Osmosis and drinking water filtration systems. Lever Style Handle. High Reach Neck Design (12" / 305mm) 360 Degree Swivel Neck. Unique Protective Spout Tip which Prevents After Drip. 2 1/4" Base Diameter (57 mm) Drilled Hole Size Needed is 7/8".
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    $219.99 Special Price $89.95
  19. 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
  20. 4 Gallon RO Water Tank-1000
    4 Gallon Water Tank for RO Reverse Osmisis Drinking Water Systems - GGN-Tank-PL4
    4 Gallon Water Tank for RO Reverse Osmosis Drinking Water Systems - GGN-Tank-PL4- Plastic 4 Gallon (15L) Water Storage Tank. 10.83" Diameter X 16.15" Height. NSF Certified. UPC #850901003514
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    $79.99 Special Price $49.99 As low as $44.99
  21. SS Stainless Steel Reverse Osmosis Storage Tank - Premium Quality
    SS Stainless Steel Reverse Osmosis Storage Tank - Premium Quality

    SS Stainless Steel Reverse Osmosis 4.4 Gallon Total Capacity Tank

    This is one of the finest RO tanks we have ever seen. The patented O-ring seal on the air stem assures "set and forget" pressure settings. Keeping the pressure in the tank set correctly is an important factor in operating your RO system. Approximately 14" high (without the tank valve) X 11" in diameter.

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    $149.99 Special Price $88.99 As low as $75.99
  22. 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.
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    $24.99 Special Price $17.99 As low as $12.99
  23.  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
  24. 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!
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    $49.99 Special Price $39.99 As low as $19.99
  25. 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.
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    $49.99 Special Price $37.99 As low as $17.99
  26. Filtamate 85 PSI APEX Inline Water Pressure Regulator With 1/4" Quick Connections
    Filtamate 85 PSI APEX Inline Water Pressure Regulator With 1/4" Quick Connections
    APEX Filtamate 85 PSI Inline Pressure Regulator. 1/4" Quick Connectors. Great inline pressure regulator to prevent excessive pressure from reaching your RO Reverse Osmosis system or other sensitive water equipment. Helps prevent water spikes, or surges, that can lead to system failure or leaks.
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    $34.99 Special Price $22.99 As low as $19.39
  27. 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.
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    $14.99 Special Price $9.99 As low as $6.99
  28. John Guest Poly Tubing 3/8" For Pure Drinking Filter Water Systems
    John Guest ® Poly Tubing 3/8" For Pure Drinking Filter Water Systems
    John Guest ® Poly Tubing 3/8" O.D. (outer diameter) For Pure Drinking Water Systems - 3/8" O.D. (Outer Dimension) High Grade Drinking Water Tubing. Speedfit quick connector compatible. For Use With Optional Drain Saddle For Air Gap Faucet. Sold by the foot. Order 20 to get 20 feet.
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    $0.50 Special Price $0.32 As low as $0.24
  29. John Guest ® Tube Cutter - TSNIP
    John Guest ® Tube Cutter - TSNIP
    John Guest ® tube cutter TSNIP - Great for making a perfect cut everytime. Helps prevent leaks by making a square end cut ensuring proper fit and seal in water connecttion fittings. A real must for any professional or discerning home owner.
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    $17.99 Special Price $12.99 As low as $10.99
  30. 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.
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    $14.99 Special Price $9.99 As low as $7.99
  31. John Guest Super Speedfit Quick Connector - Male - Elbow
    John Guest ® Super Speedfit Quick Connector - Male - Elbow
    ohn Guest ® Super Speedfit Quick Connector - Male - Elbow - John Guest Super Speedfit Quick Connectors - Male - MNPT - Sold in pairs. Price is per pair. These fittings are manufactured in gray acetal copolymer with food grade nitrile ‘o’ ring, making them especially suitable for applications involving foodstuff and potable liquids like reverse osmosis drinking water. They are equally suitable for air and inert gasses and can therefore be used on CO2 lines, pneumatic applications, and vacuum. For more than a decade, John Guest has been supplying Super Speedfit fittings to the Water Purification market for drinking water applications in homes, restaurants and industry. John Guest products are listed with the WRC(UK), NSF(US) and SK(Germany). PI480821S , PI480822S , PI480823S , PI481222S , PI481223S
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    $8.99 Special Price $4.99 As low as $3.99
  32. Teflon-Tape-100-1000
    Teflon Plumbing Tape To Seal Threaded Water Connectors
    PTFE thread sealant tape permits quick, clean, economical sealing of male pipe threads of all sizes. Reduces the risk of system contamination common with liquid and paste sealants. A must use on all male threads used in reverse osmosis and pure drinking water filtration systems.
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    $5.99 Special Price $3.39 As low as $2.75
  33. John Guest Angle Stop Water Valve
    John Guest ® Angle Stop Water Valve
    John Guest ® Angle Stop Water Valve - Makes installation a snap. Very simple to use. PPASV121208W and PPASV121212W
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    $19.99 Special Price $12.99 As low as $10.99
  34. Easy Tap Water Feed Valve for Water Filter Systems - 2000
    Easy Tap Water Feed Valve
    Easy Tap Water Feed Valve - High flow tap valve. Follow the pipe up from the shut-off valve toward faucet until you reach a coupling nut (may be all the way up to the faucet). Unscrew coupling nut. Screw brass easy tap onto previous location of coupling nut. Hand tighten and then one more complete turn with wrench. Re-attach water line coupling nut to easy tap. The valve on the side of the easy tap is the shut off valve for your new RO system. If the handle is turned clockwise all of the way, this is the "OFF" position for your new RO system. Counterclockwise all of the way is the "ON" position.
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    $19.99 Special Price $12.99 As low as $9.99
  35. Chiller Daddy CHL-750XL Under Sink Water Chiller - 110 Volt
    Chiller Daddy CHL-750XL Under Sink Water Chiller - 110 Volt

    110 Volt 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
  36. UV-SS2-1000
    UV-SS2 1 Gallon per Minute UV Ultraviolet Water Sterilizer

    304 Stainless Steel 1 GPM UV Assembly With 1/4" FNPT Connections. 6 watt Phillips UV Lamp, quartz sleeve and 100 volt transformer.  Individually boxed.  Great addition to any RO reverse osmosis system or undercounter drinking water filter system.

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    $99.99
  37. Hydrotech 25 GPD RO Reverse Osmosis System Capillary Flow Restrictor #40600040
    Hydrotech 25 GPD RO Reverse Osmosis System Capillary Flow Restrictor #40600040

    Hydrotech 25 GPD RO Reverse Osmosis System Capillary Flow Restrictor Tube #40600040.

    RED DRAIN LINE 25 GPD RO, TUBE WITH FLOW RESTRICTOR (1230/1240 SERIES)

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    $19.99
  38. 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.
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    $15.75 Special Price $12.99

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.





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


* Sierra Springs is the registered trademark of Sierra Springs, the manufacturer of Sierra Springs brand of under counter drinking water system filtration equipment. The replacement water filter cartridges, reverse osmosis membranes, water tanks, faucets and repair parts listed above are not manufactured or endorsed by Sierra Springs. Rather, these replacement filters, RO reverse osmosis membranes and DIY replacement parts are manufactured by other companies. While these replacement water filters, repair parts and reverse osmosis membranes are compatible for use in Sierra Springs under counter reverse osmosis water filtration equipment, we make no representation as to whether using these water filter cartridges and RO reverse osmosis membranes is consistent with the warranty and specifications applicable to Sierra Springs under sink drinking water system equipment.