Clean up crew

[Sam1969]

Anyone have suggestions for a clean up crew for a 90 gal tank ?

My clean up crew is small at best and almost non-existant ..

I have 2 large blue legged crabs, 5 or 6 small blue legged crabs and 3 large snails ( stupid crab ate 2 ) .
I really need somthing that will bottom feed as I have algae growing in my sand to the point where there are actually roots sticking out of the sand.

Also in my tank is a yellow tang, two clowns and an anemone

any suggestions would be appreciated

Thanks