It is interesting to note the various types of tropical fish species, strictly speaking, include both saltwater and freshwater fish. When most hobbyists speak of tropical fish species, they usually mean freshwater fish.
You can find these fish in your local pet store, or you can check out specialty shops that cater to fish tank owners. Tropical fish are born and bred in captivity, so a wild fish is rarely introduced into the tank, and only for decoration.
The different kinds of tropical fish species that fall within the tetra family are frequent residents of residential fish tanks. They are beautifully colored, and hardy enough to survive occassional missed water changes, and changes in temperature.
Prior to mixing and matching various types of tropical fish species together, however, ensure that these animals actually get along. If you don't make sure your fish are compatible, prepare for fights, fish loss, nipping, and diseased, injured fish which will spread to the rest of your tank.
When introducing a tropical fish into your home tank, speak with a store clerk about its conditions, what the maximum and minimum temperature ranges are, and what lighting is required.
Moreover, be certain to discuss food intake and the kinds of nutritional deficiencies most commonly observed with the types of tropical fish you are purchasing. Supplementing water and food is necessary to ensure fish health, longetivity, and the health of the tank.