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Neon tetra

life science Maturity 5-7 Next article →

The neon tetra, known scientifically as Paracheirodon innesi, is a small freshwater fish.

NeonTetra
NeonTetra

It belongs to the family Acestrorhamphidae, which are called the American characins. These fish are famous for their bright, glowing colors. This makes them very popular with people who keep tropical fish in home aquariums. In fact, they are among the most widely kept fish in the world. Their striking appearance helps them stay visible to other members of their species in dark waters.

In the wild, neon tetras live in the Amazon basin of South America.

NeonTetra
NeonTetra

Their range includes parts of southeastern Colombia, eastern Peru, and western Brazil. They prefer acidic blackwater streams, which are dark and filled with tannins. They also live in transparent clearwater streams. However, they do not live in whitewater rivers. These fish thrive in specific conditions, usually in water with a pH between 4 and 7.5. They also require specific temperatures to stay healthy in their natural habitat.

The most famous feature of the neon tetra is its unique coloration. The fish has a light-blue back and a silver-white abdomen. A bright, iridescent blue stripe runs along its side from the nose to the adipose fin.

Cardinal tetra & neon tetra
Cardinal tetra & neon tetra

An iridescent red stripe starts at the middle of the body and goes to the base of the tail. Most of the fish, including its fins, is actually partially transparent. This color is not permanent throughout the day. The fish can change its color based on the light. This happens because of guanine crystals in their cells that reflect light. In bright light, the stripe looks blue-green. In dark conditions, the color shifts to indigo, or even gray and black when the fish rests at night.

There are subtle physical differences between male and female neon tetras, a trait called sexual dimorphism.

Cardinal tetra & neon tetra
Cardinal tetra & neon tetra

Males are generally more slender and have a very straight blue stripe. Females often have a rounder belly and a slightly bent iridescent stripe. Sometimes, a female may look extra plump because she is carrying eggs. The fish grows to an overall length of about 2.5 centimeters. While they can live up to ten years in the wild, they usually live only two to three years in an aquarium.

History shows how these fish became so well-known. The renowned ichthyologist George S. Myers first described the species in 1936. He named the fish in honor of William T. Innes. Today, the economics of the neon tetra are massive. About 2 million neon tetras are sold in the United States every month.

Neontetra tmy
Neontetra tmy

Most of these are farm-raised in Southeast Asia. A smaller amount are collected from the wild in South America. Currently, less than 5% of the specimens sold in America are caught in the wild.

Keeping neon tetras requires careful attention to their environment. They are shoaling fish, meaning they must live in groups. It is best to keep at least six together, though groups of 8 to 12 are even better.

Neontetra tmy
Neontetra tmy

They are omnivores and eat many things, such as small flakes, brine shrimp, or daphnia. To breed them, aquarists need very specific conditions like dim lighting and a pH of about 5.5. Breeding them at home is considered quite difficult. One major concern for keepers is neon tetra disease, caused by the parasite Pleistophora hyphessobryconis. This disease can cause lumps, curved spines, and difficulty swimming. Because it is often fatal, prevention through clean water and quarantine is very important.

Neon tetras are closely related to other beautiful fish. For example, the cardinal tetra is similar but has much more red coloring.

Cardinal tetra & neon tetra
Cardinal tetra & neon tetra

There are also other species like the green neon tetra and the black neon tetra. While they look similar, they are distinct species. Understanding these connections helps scientists and hobbyists alike appreciate the diversity of the Amazonian ecosystem.

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File:Neontetra tmy.JPG
Neontetra tmy.JPG
File:NeonTetra.JPG
NeonTetra.JPG
File:Cardinal tetra & neon tetra.jpg
Cardinal tetra & neon tetra.jpg
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