My son in law came over and said his aero
tank had come apart but still worked. Apparently the aero base is a two piece affair that is
threaded together and held together by some sort of
thread locker. We thought now he could take off the ring and elongate the largest hole. For s&g i said try it without the ring. It works pretty good and has a whole lot of airflow.
The next step might be to drill out the ring to a similar shape as the opening so it can adjust from almost nothing to a huge amount of airflow. It would look better with the ring and now that you have to screw the two base pieces together you can adjust the tension of the ring.