Filterfloss or not in a cube with scrubber in back compartment???

I have a 34 g. Red Sea cube with fish, softies, lps and sps. I'm planning to put a scrubber in the back compartment.

Would you recommend putting filter floss in the back compartment as mechanical filtration OR do you want the organics to continue to flow through the tank to feed the corals. I'm concerned, however, that I would get buildup of organics in the back compartment due to flow issues.

The filter floss would likely be placed just past the overflow so the water would hit the floss before the scrubber.