In my aquarium I have 10 fish. Most of my fish are Tetras. I would like to give scientific names on all of the fish but I only know a few of them. I have 1 Bleeding Heart Tetra (Hyphessobrycon erythrostigma), 3 (unknown) tetras, 2 Bloodfins (Aphyocharax rubropinnis), 1 Von Rio Tetra (Hyphessobrycon flammeus), 2 Moon Cory Cats, and 1 Chinese Algae Eater. The tank is not the most active in the world but it's active enough for me.
I am trying to change the water more often so it is better for the fish. Usually a 10% water change every other day doesn't hurt a thing. It is very good for the fish because it replaces the trace elements that can only come from water changes. It also cuts down on the level of everyday toxins. If you want your fish to live longer this is a good idea.
I have noticed that my 2 Bloodfins are surface feeders and are more active. They are also somewhat smaller than the other fish that I have. These fish would be a good idea to liven up a boreing tank. The Bloodfins (it seems) are constantly looking for food while the others are not doing anything and are hiding.
Be sure to (at all costs) keep your fish from being able to jump out of the tank. I had a fish jump out and I discovered it a few months later behind the dresser. I had to vacum it up with the vacum hose and it's not fun discovering you had some fish jump out of the tank. I reccommend that you always keep the plastic cover over as much of the back of the tank as possible. The fish that jumped out of my tank came out of a very small opening.