Is it ok to use Zero dust on A-90 ?

Dear Mesael: First step IMHO to take care on your cartridge stylus is that your LP/records be in pristine condition every time you heard it.

Almost any cleaning fluid works to mantain your stylus, Last or Discwasher stylus fluid cares makes good job.
Depending on how many hours you play daily you will determine if the stylus needs this kind of cleaning every day or every two-three days opr every week only. In between you could use the stylus brush as Ortofon recommend.

This is my opinion and the way I make/made my stylus cartridges maintenance, other persons has different process on that subject.

Regards and enjoy the music,
Raul.

Dear Downunder: Syntax is right/spot on, that item is the one I used too for at least 15 years with superb results.

Regards and enjoy the music,
Raul.