Cleaners like any other shrimp are scavengers by nature. They will "clean up" the way any hermit or snail would. If you are being especially carefull of the amounts of food you feed the clowns, you may opt for some sinking pellets once or twice a week.
I would also not suggest brine for any fish. They may like it but it has almost no nutritional value. It's much like feeding candy bars to kids. I would instead suggest fortified flakes, pellet foods and possibley your own >>blender mush