I have been looking for the same thing and what I did was change my substrate from small/med gravel to beach pebble and put a koralia at the bottom to push some of the uneatened food/waste up and around so the filter can suck it up. My water quality got better. I also put a L-200 and a blue crayfish to worke off the buttom. I've seen the crayfish come out when the lights go out searching for food. They might be too skimkpy for what you are looking for.
