The "trash can" has a lid that turns to lock. This is the key. It allows the filter to be easily opened to replace the media.
Cut out a 1.5" hole in the lid and replace with 1.5" PVC pipe (suitable straight length or as shown with a 90degree elbow). Next drill 1/4" holes (two rows) all around the bottom of the can. Fill the can with polyester cotton. Put the lid on and you are ready to attach your new filter to the water return on your tanks.
Another implementation of a polisher is shown below.
Cheers.
