Tetras

All the Tetras belong to the familyCharacidae in the order Characiformes and are small freshwater fishes. Many tropical Tetra fish species are popular among aquarists, especially the species that are brightly colored and easy to care for in captivity.

The most famous of the Tetra species is of course the immensely popular Neon tetra (Paracheirodon innesi). This fish is found in both blackwater and clearwater streams in Brazil, Colombia and Peru. It is a peaceful fish that is commonly kept in community aquariums. It is not hard to care for and is suitable for novice aquarists. The Neon tetra grows no larger than 5 centimeters (2 inches). You should always keep at least 10 Neon tetra fishes together, since this is a schooling species that will feel very stressed if kept alone. Your Neon tetra will appreciate a well planted aquarium, but leave a space open for swimming. Floating plants that will dim the light a bit is recommended. 

A dark substrate will also help creating a less bright environment in the aquarium since it will not reflect the light. The colors of the Neon tetra will also look more vibrant against a dark substrate. Keep the water temperature between 22 and 25 degrees Celsius. The Neon tetra can live in acidic water as well as in a slightly alkaline environment, so anything from pH 5.5 to pH 7.5 will be okay. Getting a Neon tetra to eat in captivity is definitely not hard and you should strive to avoid over feeding. Choose a high-quality flake food.

An example of a less well-known tropical Tetra fish species is the Congo tetra, Micralestes interruptus. This Tetra is not as sturdy as the Neon tetra and frequent water changes are very important since this species is sensitive to poor water conditions. The aquarium where you house your Congo tetra must also be equipped with sufficient circulation. The Congo tetra is peaceful but can be a little skittish and nervous. You can make your Congo tetra less shy and decrease the stress by decorating the aquarium in a way that creates plenty of hiding spots. 

The Congo tetra should be kept with at least five other Congo tetras, preferably even more. Aggressive and bullying fish can make the Congo tetra very stressed. The Congo tetra will stay stronger in slightly acidic water, but can tolerate anything from pH 6 to pH 7.5. Wild Congo tetra is found in the warm waters of the Zaire river basin on the African continent, and your Congo tetra will therefore appreciate a water temperature in the 23-26° C (73º -79º F) range. Soft water is best, but a healthy Congo tetra will usually adapt to harder conditions as well.

A third example of an interesting tropical Tetra fish species is the Serpae tetra (Hyphessobrycon eques). This fish has a very beautiful red coloration and is therefore also known as Blood characin, Jewel tetra, Red serpa and an abundance of other names that all alludes to the decorative red color. 

The red shades vary from reddish brown to a vivid bright red. The main body is red, and so is the all the fins except for the dorsal fin which is black with a white fringe. Behind the gill cover, the body is decorated with a dark marking that is shaped like a comma.