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.


99.5% Of All Items In Stock For Same Day Shipping!

Help Choosing Filters

4 Easy Ways To Find Your Replacemment Water Filters

1.   SYSTEM IDENTIFICATION - If you do not know the name of your drinking water system, try matching it to one of the pictures shown below.

2.    BRAND NAME - If you know the brand name of your replacement water filters, RO reverse osmosis membrane or pure water filtration system you can chose from our  Brand List

3.    FILTER CARTRIDGE IDENTIFICATION - If you do not know the name of your reverse osmosis or under sink drinking water system and only know what the replacement filter cartridge looks like then try our Filter Cartridge Visual Identification Picture Guide.


Refrigerator Water Filters

Shower Filters

Whole House Water Filters

Specialty Water Filters

Water Filter Housings

Counter Top Water Filter Systems

RV & Boat Water Filters

Pool and Spa Water Filters

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