Fluval 305

I use... course sponges that came with it on the side... bottom and middle tray are the ceramic bio rings, and the top tray has filter floss in it. That on my planted 46g tank.

I keep the carbon ONLY for removing medicine.
 
I use... course sponges that came with it on the side... bottom and middle tray are the ceramic bio rings, and the top tray has filter floss in it. That on my planted 46g tank.

I keep the carbon ONLY for removing medicine.
I do it the other way around, floss on the bottom and ceramic rings on top.
 
fine ceramic rings... filter floss... carbon(maybe)... coarse ceramic rings
 
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