I think there is a good chance it is dirt/dust as well. I just don't know.

Do you think I should vacuum to waste or to recirculate? I've been advised before to vacuum to waste, but it seems to REALLY take a lot of water out of the pool. In fact, I may need to stop, re-fill, and then continue several times to keep the water level above the skimmer. On the other hand, if it is dirt/dust, and if it is going into suspension (and thus, I would assume, through the zeo sand filter system), vacuuming on recirculate probably isn't going to help.

Also wondering about my vacuum head. Around the edges, it is covered with bristles, but it has a hole in the middle that draws in the water. This is very counter-intuitive for me, as it would seem to stir up the gunk before it can be pulled in by the intake. I've seen vacuum heads with no brushes, and just rollers that keep the head about 1 cm above the pool surface. These seem like much more sensible items to use for a problem like this. Thoughts?

Thanks, again, Watermom for all the help!