Every time I vacuum all of the dirt out of the pool, it would be spotless, but a few hours later after the pump would run, the bottom is covered with some type of fine dirt particles. (see pic below) I tried replacing all of the cartridge filters and it still does it. I even bypass passed the filter and it still does it. I’ve had the system checked three times for leaks and they say it has no leaks. Any idea how to fix this? This is an in-ground fiberglass 24,000 gallon pool with Hayward C4030 filter and Pentair 340038 1 HP pump. I supply jet and 1 return skimmer. Drain line is plugged.

Thank you for your help.