well if he really wants a shark and fish then it will be a while before he can get a shark for that size of aquarium, and if he did then no triggers, puffers, angels, or wrasses. If wants to give up the idea of sharks then he can have those fish. But just wondering how many marbled cats has anybody seen. From what Ive seen looking for them online they are pretty rare. It would be cool if they were more avalible but in Aquarium Sharks and Rays he says they are not common in the aquarium trade. Still the stocking list is up to ackermsb. We are just here to give input.
If ackermsb wanted to wait for the marble then I would put an eel, lion, tangs, or any other medium sized fish. Small fish and inverts would be eaten by the eel. If there wasn't a plan for a marble then triggers,lions, puffers, eels, tangs, and anything else as long as they are compatible.