I too have been battling what I now believe to be silt or pollen. Originally, I thought it might have been the mustard algae and I took the precaution to shock heavily for 4 days. However, the problem persists. I still get some brown deposits on the floor of my pool.

I have also been getting the white scaley things floating on top. You can barely see them unless you catch it at the right angle and then you can see all the particulate on the surface. My suspicion is that my sand filter is not filtering this pollen/silt out and it just keeps running through.

My next step is to take apart my sand filter (which I have never done) to make sure that the sand is in good shape. Beyond that I'm sure it will eventually get vacuumed out.

Good luck!

Riles