Why won't my pool get clean?

[rilesworld]

I have read that post before, and was curious about that type of algae. Is there anyway to determine whether it is silt or algae (without a microscope). I would hate go through the extreme shock process if it wasn't necessary.

BTW I have a couple of other points. The bottom of the pool does feel a bit slimy (bad news), but this hasn't seemed to get any worse over the past month with me maintaining 3-6ppm Cl. It just won't go away. In other words, I don't get the impression that anything is multipling. Not sure if that information is useful, but it might help.

Riles