Filter Socks

[Jaws]

So I tried adding a filter sock to my overflow the other day to try and trap as much detritus as possible. It worked fine for a couple days and then started overflowing after about 4 days. When I pulled it out it was kind of brown and slimy almost like it had been lying in muddy water. Is this normal for them to clog up that quickly? My water quality is pretty good and I guess I'm just having a tough time believing there is that much crud floating around in my tank. Anyone else have any filter sock experience? Thanks.