A few questions....

My room mate moved out and left me his 50 gallon freshwater tank with 2 fish. My first question is about the sucker fish-Patrick-he's almost 12 inches long-does he need to be in a larger tank? My second question is about Draq-I have no idea what kind of fish he is. I asked my room mate and he said he was from Africa...I seriously doubt that. He's about 9-10 inches long-and about 1-2 inches in height. He long and skinny looking with a silver belly and grey on the rest of his body. He has 9 fins in a row that lead down his back into his tail fin. On his belly close to his tail fin he has two small fins and there are two larger ones on his belly close to his head. You can see his ribs down his sides. We used to have two angel fish-Draq ate them and then a hermit crab that we got after the angel fish. So, any ideas on what kind of fish he is, important care information about him, and/or possibly compatible fish???? Any imformation at all will be greatly appreciated. Thanks!