The Emperor tetra is found the streams and rivers of western Colombia

Colombia

Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...

 including the Rio Atrata and the Rio San Juan.

In the aquarium

The Emperor tetra is a placid aquarium

Aquarium

An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

 fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

 and will be disturbed by more boisterous species. It grows to 7.5 cm. It prefers a pH

PH

In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

 of 6.5, a hardness of 50–100 mg/l and a temperature of 23-27 C.
It does not school as readily as most tetras, and a single fish, or a pair appears happier than with most tetras.

Foods and Feeding

The Emperor Tetra is an omnivore, eating both animal and vegetable food. Any good flake or pelleted fish food is a good basis for its diet. It will benefit from live food like Daphnia and wrigglers (Mosquito larvae) as well as frozen fish food including frozen bloodworms.

Gender

The males and females are easily differentiated. There are many differences; perhaps the easiest one to be sure of is the tail. The male has a three pronged tail with the centre black part extending beyond the rest of the tail while in the female the centre black part only reaches as far as the clear part of the tail.

Breeding

In a large well planted aquarium a single pair of Emperor tetras will often breed without any extra stimulation. If there are no other fish, some of the babies may survive especially if the parents are well fed. In a large, well planted aquarium the babies will find some useful natural food in the form of protozoa

Protozoa

Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...

, algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

, etc. Screened Daphnia will provide them with more nourishment as they grow, and dry fry food can be used.

Appearance

The purple hue of these tetras will be more apparent in an aquarium with floating plants on the surface and relatively subdued lighting. If the aquarium is too bright, the yellow coloration will dominate.

Sources

• Encyclopaedia of Aquarium and Pond Fish (2005) (David Alderton
  David Alderton
  David Alderton is an English writer specialising in pets and natural history topics. Growing up in a home surrounded by pets, he originally trained to become a veterinary surgeon. An allergic dermatitis acquired in his final year of study forced a change of career however, and so led him into the...
  
  )
• Emperor tetra fact sheet: http://www.bettatrading.com.au/Emperor-Tetra-Fact-Sheet.php