You should start off with a Iranian Desert Shark because I heard those fishes would make your tank explode with coolness. Also you should probably add some Nigerian Mud Penguins as well, they have the ability to swim so it's all fair game.
Was planning on getting but they dont sell shark. Sad Story.
My Brother had a Barramundi, it's like a big ass bass very aggresive use to feed it goldfish lol,
depends if you want a small family of fish if u fail to feed them a day or two they can turn on eachother reguardless of which fish they are pretty common, but i'd recommend getting a small fish that can get big much more interesting more like an actual pet than a bunch of eye candy,