Im buying a canister for the first time and i think i got the idea of what i should put in and in what order , on the bottom is biological filtration and the trays above that is mechanical ? Correct me if im wrong.... But what biological media should i use? Ceramic rings ? Bio balls ? Seachem matrix ? Really dont know
If there were 3 or 4 trays what would you fill them with and in what order ?
Thanks in advance