9.75" X 2.5" Filter Cartridges

This is the most common and popular size for water filters. Cartridges in this list will fit the products of many filter makers. There are two essential styles—radial, where water flows from the outside, through the cartridge wall, into a hollow center core, and axial, where the water enters the filter at the end and flows the full length of the cartridge to exit at the cap end of the vessel.

Important note: If your current filter uses a radial style cartridge, you can replace it with an axial, and vise versa.

In general terms, radial cartridges are carbon blocks and axial cartridges contain loose or granular filter medium.

Here’s what they look like:
At left is a standard radial carbon block. It’s the MatriKX pb-1 lead removal carbon block. Water flows from the outside, through the wall, to the inner hollow core.

All MatriKX carbon blocks on the cartridge menu look like this (except for color variations).

We also stock carbon blocks by Pura.

At right is the Di-Tech Nitrate Removal Cartridge. It’s an axial flow cartridge with granular ion exchange medium. Water enters via holes in the bottom of the case and exits through the hole in the top. All Di-Tech cartridges on our menu are of this style, though colors will vary.

We also offer our own generic axials in several styles, plus some high quality cartridges from Flowmatic and other top manufacturers.