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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Aqua Flo "D" series upgrade from the "E" series

Aqua Flo "D" series upgrade from the "E" series

Aqua Flo, Puretec & Novatec ® "D" series upgrade from the standard "E" series.   

Adds 2 more stagees of filtration.  One is a 6" Extended Contact GAC post filter.  The second is an added phosphate and carbon filter.

  1. 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
  2. Pentek SW-1A # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench
    Pentek SW-1A # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek SW-1 # 150539 SW1 Slim Line Water Filter Housing Spanner Wrench Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. SW-1 Water Filter Housing Wrench. Fits 4" Slim Line Housings. (Slim Line Housings Have A 3 1/2" diameter "O" Ring) Ametek # 150294 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. Fits most standard style RO systems. Replaces 150294. 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. Order New O-rings And Be Sure To Lube Them With Dow 111 Silicone Sealant To Prevent Leaks Learn More
    $9.99 Special Price $6.99 As low as $4.99
  3. 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

    Learn More
    $17.99 Special Price $9.99 As low as $6.49
  4. Pentek TS-101 # 155083 TS101 Inline Phosphate & GAC Carbon Water Filter
    Pentek TS-101 # 155083 TS101 Inline Phosphate & Carbon Water Filter Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands
    Pentek TS-101 # 155083 TS101 Inline Phosphate & Carbon Water Filter Compatible With Culligan / Ametek / US Filter / Plymouth / Kleen Plus / American Plumber / Bruner & Many Other Brands. TS-101 Inline Icemaker Water Filter. Phosphate Crystals & Carbon. Inhibits Scale Buildup. 1/4" FNPT Without Fittings. 6 per case, sold individually. Ametek # 155083 Learn More
    $19.99 Special Price $14.99 As low as $11.99

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.


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