I will be setting up a 150 FO, with 2 tangs , foxface, flame angel, 2 perc. clowns, and MAYBE a royal gramma. What I am wondering is how much is TOO MUCH?(for a clean-up crew) Many of these fish eat algae, so I don't want to remove all of it...??..Will the cleaner shrimp and hermit crabs bother...