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Possibly if enough water is running through it. Maybe 2:1, but again, its depending on your unit and its membrane. I wouldn't expect that from a buddy unit.
I've run:
A biopellet reactor, carbon, gfo, matrix.....you name it in my AIO tank. As it "matures", you'll find that less stuff will be needed.
Right now, I'm only running a fuge and and a skimmer in mines.
I think it's a matter of necessity. For a new cycling tank....nothing, just some sponge/floss to catch the junk that'll be floating around.
Later on when some fish are added, you could go with carbon just to keep the water clear. That with a skimmer should hold you down for a while.