Multifasciatus are great little fish, and their small size means you can have a few in a 10 gallon tank. They're colony fish and do great in groups, though in this size tank you need to be careful of aggression once they start breeding. Sand substrate is great because it's easy for these little guys to dig, rather then having to grab one boulder at a time. Multifasciatus come from areas of lake Tanganyikans thick with shells, and that means you can't have too many - 3 shells per fish is a reasonable absolute minimum, and more is better.
Different shellies do have different habits. Brevis, for example, come from areas where shells are very sparse, and one per fish is fine - in most cases a pair would even end up sharing a single shell.