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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Delta Fresh Water Filters

Delta Fresh Water Filters

Delta Fresh US-1, US-2, US-3 Reverse Osmosis Undercounter System Replacement Water Filters And Reverse Osmosis Membranes.

Delta Fresh Reverse Osmosis Systems use slim-line replacement O-rings, housing wrenchs and replacement filter housing sumps. They originally came with a 3.2 gallon tank. We carry all the repair parts, faucets, tanks, filters, RO membranes, valves, tubes and connectors for all of the Delta Fresh reverse osmosis systems.

Minimum filter change is every 6 months for the sediment prefilter and every 12 months for all carbon filters.  Change more often if your usage is higher than normal or you have bad incoming source water.

RO reverse osmosis membranes need to be periodically monitored with a TDS Tester to check the efficiency of rejection of the ro membrane.  Use our simple online TDS recetion calculator to know when it is time to replace the membrane.

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.

* Delta Fresh ® is the registered trademark of Delta Fresh, the manufacturer of Delta Fresh ® brand water treatment equipment. The replacement filters and membranes listed above are not manufactured or endorsed by Delta Fresh. Rather, these filters and reverse osmosis membranes are manufactured by other companies. While these filters and ro membranes are compatible for use in Delta Fresh ® reverse osmosis systems and water treatment equipment, we make no representation as to whether using these filters and membranes is consistent with the warranty and specifications applicable to Delta Fresh ® water filter equipment. This includes compatible replacement sediment water filters, replacement Carbon Block Water Filters, GAC Carbon Filters, AICRO Inline Post Filters, RO Reverse Osmosis Membranes, Sediment Pre Filters, faucets, water tanks, valves, pumps, UV Ultraviolet and water testing supplies.