Review on Penn Plax Smallworld Filter Cartridge by Lisa Lopez

Three things to know about this filter: 1) so loud. omg so loud I had to replace the air pump with another one (which I bought from PetSmart for $92) that keeps all the air under the filter until it erupts with a horrific burp that startles everyone, including fish, who hears it. I had to drill additional holes to allow air to escape more easily. 3) You can't thread the included air hose through the tiny hole in the bottom of the filter so I had to take a drill and enlarge the hole. What a herd of pain in the buttocks.