I wanted to use two cylinders packed with bio media and an air stone at the bottom of each one. In theory, it will 1. bring water from the bottom to the top and 2. add bio filtration by giving a good gas exchange. I am new to internal filtration, would this work or would it be a waste? I have 90G that I wanted to do this with, its 25" tall and figured it could potentially add a lot of bio filtration. Any opinions? I tried to do a search to see how many have tried this but didn't know what it was called, sorta works off of the sponge filter concept.