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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  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 16" high X 11" diameter. Metal tank is 15" high X 11" diameter. # 12302003.

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    $439.99 Special Price $389.99 As low as $369.99
  2. 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
  3. Pro Products Sani System RO & Water Filtration System Sanitizer
    Pro Products Sani System RO & 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 $2.99
  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. 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
  6. 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 $99.99
  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.
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    $24.99 Special Price $17.99 As low as $12.99
  8. 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.
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    $69.99 Special Price $49.99 As low as $29.99
  9. Easy Tap Water Feed Valve for Water Filter Systems - 2000
    Easy Tap Water Feed Valve For Water Filter Systems 3/8" Feed Tube
    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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    $16.99 Special Price $8.99 As low as $4.99
  10. John Guest Super Speedfit Quick Connector - Male - Elbow
    John Guest ® Super Speedfit Quick Connector - Male - Elbow
    John 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
  11. 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 : 1.75 Gallons Per Hour (6.6 Liters 5L/H (<10C) Continuous Cold Water Output(cc/hr). 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 $395.00 As low as $354.00

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.





* ARRROWHEAD ® IS THE REGISTERED TRADEMARK OF ARRROWHEAD , THE MANUFACTURER OF NOVATEK ® BRAND WATER TREATMENT EQUIPMENT.  THE REPLACEMENT FILTERS AND MEMBRANES LISTED ABOVE ARE NOT MANUFACTURED OR ENDORSED BY ARRROWHEAD.  RATHER, THESE REPLACEMENT WATER FILTERS AND REVERSE OSMOSIS MEMBRANES ARE MANUFACTURED BY HYDROTECH - CANATURE, THE ORIGINAL MANUFACTURER OF ARRROWHEAD UNDER COUNTER REVERSE OSMOSIS DRINKING WATER SYSTEMS.  WHILE THESE FILTERS AND MEMBRANES ARE COMPATIBLE FOR USE IN ARRROWHEAD ® 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 ARRROWHEAD ® UNDER COUNTER DRINKING WATER SYSTEM EQUIPMENT.