Hi, I purchased a 55 gallon aquarium to introduce my son to the hobby, I have not had a aquarium for 35 yrs. Things have changed since I was young! The Fluval 303 canister filter that came with the setup. It had the Bio max on bottom,the carbon in second level and the foam pads (2) on the top,I put it back together after cleaning it in the same order. I then read on line in the Fluval manual that the bio max should be in middle and carbon on bottom. Any comments as to what order the compartments should be in canister? They did stress the foam pads be on top to protect the impeller from any larger matter that may find its way in filter. Would there be any reason to run a second filter in this planted community tank?