I have recently purchased an FX5 canister filter and don't see anywhere on how much media to use. I bought the Fluval brand box of bio max (1) and placed in the middle rack and the 3pack carbon and put two of those in top rack, also put some more carbon pellets in bottom rack. It doesn't seem like it is enough. I have seen somewhere where they have filled those racks all the way to about one half inch from the top with the bio max and so Iam trying to find out how much bio max and carbon to use.Also does anyone know about carbon pellets and wether or not it is not as good as the other smaller stuff?Also I hear different things about how often you should clean the filters and replace carbon, some say they can go as much as 3 months, I know it depends on your stock , mine is 3 large (7 to 8 inch) S/A and 5 small to med (3 to 4 inch) S/A cichlids in a 125 gal, doing 30 % water changes weekly and also have 2 400 emperor hob's. Thank you for all your advice.