I know that thing was pure white two months ago. I need to learn the science of exactly how these work, bugs me when I don't get it. Perhaps I'll find an article on advanced aquariumist or what ever you call it.
It will be attached to my 24gpd coralife pureflow II which is running as we speak. Not sure if it is worth the money to keep it running though as I seem to be going through prefilters very quickly. I am counting gallons to see exactly how much I can get out of it and picked up several spares last time I was at that pet place.
I also still need to figure out what type of hose to use that I can keep under pressure and keep warm, so that I can preheat my water before it goes into the RO so I can get better GPH out of it. I've seen in several places where people have suggested running a hose through a buck that was filled with water and had a heater in it. So I went out a hose, only read the packaging when I got it home and hooked it up.
In hope depot I saw a "leakproof" from a company called fiskars, it was $17.98. Then there was a hose from Good Year that was a commercial premium rubber hose, was a bit more expensive I think, I forget how much. I figured that should work as well
Jon