the little electric yellow and a small auratus are really nice. They like tubes, i have a system of pipes i add to occasionally (decorative fish store ornaments) and they love to explore it, and pop out of it from all angles. The gold fish is from the county fair, (lol) and hes pretty damn huge, at least 15 times the weight of the auratus. And that goldfish (curly) eats non stop. The firemouths are a good choice too, the one i have (had two but a catfish i had ate it) is about the size of the goldfish, him curly, and my tinfoil barb are the three 'big' fish in the tank. The firemouth will threaten and chase the two other big fish when its feeding time, but he never attacks anything, just a peck to get the food first. The zebra ( i think hes a zebra, his name is chip cause he looks like hes covered in chocolate chips) is a fast grower, and a nice fish. Just make sure you have an established tank first, with your normals, and the cichlids will not cause trouble