In my tank I have a Rainbow Shark (awesome fish) and two Amano Shrimps to be my clean up crew. This system works perfectly because the shark can be picky about what leftover flakes he eats. He only eats certain colors and sizes of flake. My shrimps, on the other hand, come and eat what the shark won't after the lights are out. They even use the same cave, the shrimps sleep in it during the day and the shark sleeps in it at night. It's a beautiful system! Tell me about your clean up crew!