not sure, but some things that effected me with a lot of that very fine almost pixy dust stuff is new house construction behind me and pollen in the air in early spring for a few weeks.Farmers in fields and after all day week long heavy rains.Most is too fine for sand filter to stop.
I have found that once I cover the pool with the solar blanket, it helps in in containing that stuff into smaller piles around pool, and I clean with the pool blaster, instead of it being scattered on floor,somehow the cover and return flow contain that stuff instead of wind across water surface circulating it around.Take a pool brush and just brush some of that stuff lightly once,if you create a dusty looking cloud that goes away and the floor in that spot looks clean, just to come back a little while later with more or less of that stuff not much you can do but continue to clean.