My uncle is giving me a 55gal aquarium which already has a 3 year old tiger oscar, a huge pleco, and a red belly piranah... i dont know if the piranah should be there but its been doing well for about two years so i will keep the three fish that he's also giving me. He will give me all equipment required but i want to know what other cichlids I can put in the tank. i will also be buying another oscar so take that into consideration too.