Anycubic Photon fan duct, backplate, external filters and adapters

One of the minor problems of the printer is the filtration.
The first fan leads the smell downwards, the LED fan blows it forward in your room.

The filter size is poor.

Even with a bigger filter at the rear plate there is still some smell blown by the LED fan as they are "sharing" the air.

I created this fan duct including some adapter which leads the air complete to the backplate.
Next step ist the CAD of the backplate an adapters for bigger fans, exaust pipes and so on.
The filter