TwistedPenguin;3481802; said:I love all 3 of my FX5's. Media choice would depend on whether you want it mainly for biological or mechanical filtration. The big sponges in all 3 baskets and nothing else would still be excellent biological filtration and would work best for mechanical (like for Oscars). If biological filtration is your main concern then you could use the sponges plus media stones in the middle of the 3 baskets.