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Microline Filters S7125 and S7128 are Different Size - Proprietary
Last Updated: 04/05/2018
Customer Writes: I have an aquapro TFC-4 RO system installed in my home. I need replacement filters ( S7125 and S7128 ) and am having a hard time locating them. I see filters labeled as for TFC-4 on your website, but I'm not sure if they are what I'm looking for. Can you please confirm if they are compatible?

*As shown in the photo below, the two styles are very different.

The third party unit ( there are about a dozen proprietary "Brands" which use a Microline S7125 GAC Post, and S7128 carbon sediment prefilter which you will NOT Find on our website. These are not directly interchangeable, but there is a way to "adapt" your system for use of "standard", long, thinner versions that are more readily available, and generally less expensive to purchase.
The dimensions of S7125 and S7128 filter are 2 and 3/8 inches in diameter and 9.5 inches long (if you count the spout at the top.)
And the 50 gpd membrane, S1448RS, is the proprietary ( Short ) version of the Microline S1229RS, commonly used ( and included in our SET MTFC335 ).

* We stock and sell the common Microline 11 1/2" length replacement filter cartridges. To adapt from having to use the shorter proprietary version, and start using the longer "standard" version, you must replace the sump housings ( change all 3 if changing the Membrane too ) with longer version of the housing ( our PN S7029-09 ).

see Microline New Sump Housing S7029-09

Here is the Short Fatter Filter ( S7125 ) compared to the Longer Microline S7025 we sell:

S7025 and S7125 Compared

Microline Filters For Sale Here"

** Other proprietary versions use part numbers S7228, S7225, S1340RS ( such as models sold by Intermountain Soft Water ).
And the standard filters ( S7025, S7028 ) and membranes ( S1229RS ) will not fit / work with the proprietary models, unless you change the Sump Housings ( all 3 ) to S7029-09.

Another example is "Water Care Clear Flo", with CS7111 ( replaced by S7011 if all SUMP Housing replaced ), CS7125 ( S7025 ), CS7206C-JG ( S7206W-JG ) and 100 GPD membrane CS1774RS ( we recommend the 50 GPD, S1764RS )

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