Well, it's time to take out the carbon that came with my Marineland C360. I wanted to replace the carbon bucket with some more ceramic rings like what came with the filter. My LFS did not have the Marineland ceramic rings, so I bought some EHFI MECH. It pretty much looks the same, but the rings are smaller. For some reason, Eheim considers this a mechanical filtration. Does anyone have any experience with this stuff? It certainly doesn't seem like mechanical media to me. It's filter maintenance day and I think I'm going to throw some in. Thanks!