<< may be a good place to start. Most lions are nocturnal by nature and only a few types will actuall be active during the day. You should also choose by max. adult size as well. Many are very large growing species and would outgrow a 75 gal
in time. Once you have decided on what type of lion strikes your fancy it may offer additional insights.
Most however are very similar in care and tank mates. The main rule being, never house any other fish that is small enough to fit in it's mouth. Most if not all decorative shrimps and crabs are out as well.
They will also do better in an FOWLR
setting as it offers a much more natural environment for most lions as it provides for hiding places and allows it to maintain it's "predatory" behavior rather than being in an open tank.