Purex Alpha plus Inline Dust Filter

Hi

I am having issues with my Purex Alpha, the initial filter (dust not HEPA) is becoming inefficient in about 2 weeks of use. I laser Opal PETG 2mm sheets and i can see a lot of build up in there.

I was thinking of adding another inline dust filter before the Purex but wondered if anyone has any experience with this, or better work arounds, anything i should think of? Or is this likely the best solution?

I’m new to laser cutting and looking for advice!