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Lancaster CRO-312 Reverse Osmosis System Water Filters

Lancaster CRO-312 Reverse Osmosis System Water Filters

Lancaster ® CRO-312 Reverse Osmosis Compatible Replacement Water Filters And Reverse Osmosis RO Membranes

Compatible Replacement Filters For:

Lancaster ® CRO-312 Reverse Osmosis S7028 Compatible Replacement Sediment / Carbon Block Water Filter

Lancaster ® CRO-312 Reverse Osmosis S7025 * Lancaster ® Clack ® Compatible Replacement GAC Water Filter

Lancaster ® CRO-312 Reverse Osmosis S7206-06C & 7206W Compatible Replacement Polishing Water Filter

Lancaster CRO-312 ® Compatible TFC 24 GPD RO Reverse Osmosis Membrane 

Lancaster CRO-312 RO system has a water line connecting the bottom portion of the RO Membrane Housing to the Prefilter at the top of the RO manifold. to  This system uses a standard size and style membrane.

  1. MICROLINE-CLACK - RS-21-CB5-EB Compatible Carbon Block Water Filter S7028 (A1013475) - 1000
    RS-21-CB5-EB Microline / Clack ® Compatible Carbon Block Water Filter S7028 (A1013475)
    RS-21-CB5-EB Microline / Clack ® Compatible Carbon Water Filter For Reverse Osmosis RO Systems. S7028 Compatible. (A1013475) Be sure to replace the o-rings in all older systems. Be sure to use Dow 111 Silicone sealant to help prevent leaks. Learn More
    $23.99 Special Price $14.99 As low as $11.99
  2. MICROLINE-CLACK - S7025 Carbon GAC Water Filter (A1013473)- 1000
    S7025 Microline / Clack ® Carbon GAC Water Filter (A1013473)
    S7025 Microline / Clack ® GAC Carbon Water Filter (A1013473) For Reverse Osmosis RO Systems. Pre / Post filter. Be sure to replace the o-rings in all older systems. Be sure to use Dow 111 Silicone sealant to help prevent leaks. Learn More
    $17.99 Special Price $11.99 As low as $9.79
  3. Omnipure K2333 Inline GAC Carbon Replacement Water Filter -1000
    Omnipure ® K2333 Inline Carbon Water Filter
    Omnipure ® K2333 2" X 6" GAC Inline Water Filter With Quick Connect Fittings. 50 per case, sold individually. Note: The connectors come with a "plug" in them for sanitary reasons. This keeps dirt and debris from entering the connector prior to use. To remove the plugs you push in on them and hold down the outer plastic ring, and then pull the plug out. The same method is used to remove the tubing when it comes time to replace the filter. 50 per case, sold individually. Order a case and save even more. Learn More
    $19.99 Special Price $12.99 As low as $9.49
  4. DESAL TFM-24 RO Reverse Osmosis Membrane #1220189 GE Osmonics Pentair - 1000
    Desal ® TFM-24/Filmtec TW30-1812-24 RO reverse osmosis membrane # 1220189 GE Osmonics Pentair
    Desal ® TFM-24 GE Osmonics - 24 GPD (gallons per day) TFC Style Reverse Osmosis RO Membrane - Fits Standard Size Membrane Housing. # 1220189. Pentair ® /G E Osmonics ® 24 GPD Thin Film Reverse Osmosis Membrane Model # TFM-24 - Part # 1220189. Compatible with Dow Filmtec, WaterFiltersOnline.com and CSM RO Reverse Osmosis membranes. THE TFM-24 HAS BEEN DISCONTINUED AND IS NO LONGER AVAILABLE. IF YOU ORDER THE TFM-24 YOU WILL RECEIVE THE FILMTEC TW30-1812-24. Learn More
    $89.99 Special Price $56.99 As low as $39.99
  5. Amtrol ® RO 4 Reverse Osmosis Replacement Accumulator Water Tank
    Amtrol ® RO 4 Reverse Osmosis Replacement Accumulator Water Tank
    Amtrol ® RO 4 RO Replacement Tank for Reverse Osmosis Systems. 4.4 Gallon (15" high X 11" diameter - including base) SS Stainless Steel Connection Stem - Connection Size: 1/4" MNPT - Valve Optional. Ball Shut Off Valve Optional. Learn More
    $79.99 Special Price $59.99 As low as $49.99
  6. Microline / Clack ® S3069 water filter housing o-ring
    Microline / Clack ® S3069 o-ring
    Microline / Clack ® S3069 o-ring. Fits Microline - Clack sump #S7029. Replace O-rings when changing the filters to help prevent leaks. Be sure to replace the o-rings in all older systems. Be sure to use Dow 111 Silicone sealant to help prevent leaks. Learn More
    $8.99 Special Price $5.99 As low as $3.99
  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

    Learn More
    $5.99 Special Price $3.99 As low as $1.79
  8. Microline - Clack Filter Housing Wrench S3072
    Microline - Clack Filter Housing Wrench S3072
    Microline - Clack Filter Housing Spanner Wrench - Fits standard Microline and Clack Systems. #3072 Learn More
    $12.99 Special Price $8.99 As low as $6.99
  9. 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
  10. 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
  11. Pro Products Sani System Sanitizer
    Pro Products Sani System Sanitizer
    Pro Products Sani System Sanitizer. 0.25 or 0.5 fl. oz. concentrate. 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. 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. Sani-System is now NSF certified! This is the best sanitizing solution available anywhere! Stock up and save. Learn More
    $7.99 Special Price $4.99 As low as $2.49

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.


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