different clean up members do different things so diversity is key. start with a healthy pod and worm population. Add in some scarlet reef hermits, cerith snails, trouchas snails, stometella snails, and turbo's if you don't mind minature bulldozers in your tank. for the sand bed I like a couple fighting conch's and some nassarius snails.
BTW the fish in the tank do matter since if your talking about an agressive tank then all of the above will be "lunch" instead of a clean up crew.