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Learn to increase the GPD capacity size of your reverse osmosis membrane

We frequently get questions about increasing the GPD capacity of the reverse osmosis membrane on RO systems.

This will not only increase the daily production capacity, but more importantly, it will increase the speed at which the RO water is produced. This allows for better assurance that there is adequate water available when desired, even during heavy use times of the day. It is also important to have adequate flow available for the ice maker when it calls for water. A starved ice maker can burn out. Be sure to read more about Flow Restrictors.

This is the same basic procedure for updating a "proprietary" RO membrane to a standard size and style of membrane. Many owners of "proprietary" style RO systems convert their systems to use the standard size and configuration that will be less expensive and easier to find.

The membrane upgrade is very simple on most reverse osmosis systems. Simply replace the membrane with the desired capacity and the correctly sized matching flow restrictor. These must be matched to keep the proper balance between waste water and pure water. Mis-matching can either cause excessive waste to the drain or premature membrane fouling.

This is also a great conversion if your reverse osmosis system has a non-standard size membrane and housing. In this case, simply replace your housing with the standard size one shown below. This works on all systems other than those that use a "manifold' system. A manifold system is one that makes the connections in the plastic head without using tubing to connect the separate components. Manifold systems must use the original size membrane.

  1. TW30-1812 RO Membrane Housing- 304 Stainless Steel- SS-1812- 1000
    TW30-1812 Membrane housing - 304 Stainless Steel - SS-1812
    TW30-1812 Stainless Steel RO Membrane Housing - High detail and quality. This high end Stainless Steel RO Membrane Housing fits standard residential TW30-1812 RO membranes, which is the most common size of reverse osmosis membrane for home RO systems. This SS Membrane Housing is the finest quality housing we have ever seen for residential RO systems. Food Grade 304 Stainless Steel.
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    $129.99 Special Price $89.99
  2. Standard Size RO Reverse Osmosis Membrane Housing
    Standard size RO reverse osmosis membrane housing
    Standard size RO reverse osmosis membrane housing - 90° Ports with 1/8" FNPT Threads - Includes New O-rings and 3 90° 1/4" Jaco Fittings For 1/4" O.D. Tube. Upgrade to the optional John Guest Quick Connectors. The end with a single port is the inlet feed water. On the end with two ports the center port is the permeate (product) water. The offset port is the brine (waste).
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    $34.99 Special Price $19.99 As low as $16.99
  3. Be sure to order the correct Ml flow restrictor to match your reverse osmosis membrane.
    Inline RO reverse osmosis membrane flow restrictor

    Premium inline reverse osmosis membrane flow restrictor - Keep your system operating correctly by replacing worn flow restrictors.  Reverse Osmosis systems use pressure differencials to power the reverse osmosis process.  A worn flow restrictor will alter the proper balance. Our in-line capillary flow restrictors are very simple to install.

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    $33.99 Special Price $19.99 As low as $15.99
  4. DESAL - TFM-18 RO Reverse Osmosis Membrane #1220188 GE Osmonics -1000
    Desal ® TFM-18/T112-18 RO reverse osmosis membrane # 1220188 GE Osmonics
    Desal ® TFM-18 GE Osmonics - 18 GPD (gallons per day) TFC Style reverse osmosis membrane - Fits Standard Size Membrane Housing. # 1220188. Pentair ® / GE Osmonics ® 18 GPD Thin Film Reverse Osmosis Membrane Model # TFM-18 - Part # 1220188. THE DESAL TFM-18 HAS BEEN DISCONTINUED AND IS NO LONGER AVAILABLE. IF YOU ORDER THE DESAL TFM-18 YOU WILL RECEIVE THE T112-18.
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    $89.99 Special Price $49.99 As low as $39.99
  5. 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
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    $49.99 Special Price $37.99 As low as $17.99
  6. 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
  7. 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
  8. 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
  9. Reverse Osmosis membrane water pressure meter kit
    Reverse Osmosis membrane water pressure meter kit
    Reverse Osmosis membrane pressure meter kit - Add this kit to your standard reverse osmosis system membrane housing to determine the incoming water pressure that is being applied to the RO membrane. This is a great way to monitor the pressure on the membrane. Easy installation.
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    $32.99 Special Price $19.99 As low as $17.99
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.