Your filter should pick up that fine stuff unless it's been damaged.

You know, you CAN go to a different type of filter if you want. Sand never needs replacement and gets better as it gets older and dirtier, but allows the biggest particles through. DE gives the finest filtering but you need to add DE powder regularly and there's some year-end maintenance.

Whatever you get, get a filter with a max capacity GREATER than your pump's output. Too big a filter for the pump is fine--too small is a problem.