Amazing Blue Lines of Neon Tetras

neon tetras
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Neon tetra is a tiny freshwater fish that can reach up to 3.5 centimeters long. It originated from wetlands of the Amazon including Eastern Peru, Western Brazil, and Southeastern Colombia. It’s famous among aquarium fanatics because it exhibits bright coloring. Aside from that, caring for them is relatively easy. They have a lifespan of up to ten years in the wild and up to five years in captivity. Its counterpart is cardinal tetra.

Determining the gender of neon tetras is quite challenging because they look the same. A remarkable determinant is the female neon tetra has a round body and slightly curved blue line compared with the male which has straight blue line and slender body. In the case of the female, the cause of curving of the blue line and having rounder body is due to the egg sack for reproduction.

If you are planning to obtain them, make sure that you perform acclimation first because neon tetras are sensitive to sudden water temperature swing.

This fish species has a distinct characteristic. I was trying to catch them to clean the tank. They play dead when on the fishnet. I was shocked when I witnessed this instance for the first time. Don’t worry because they do that for only a few seconds. You can see for yourself.

Environment Requirement

  • ¬†Amazon environments have a temperature range of between 21 – 27 degrees Celsius (70-81 degrees Fahrenheit). The temperature must be the same with your tank to ensure good health of the neon tetras.
  • Water parameter:
    • 5.0 – 7.0 pH
    • 1.0 – 2.0 KH
  • They are not picky eaters. They eat the same line of food that guppy fishes take. A varied diet works best for them.
  • Neon tetras are peaceful fishes. Avoid introducing fishes that are aggressive in the tank. They protect themselves from the aggression of other larger fishes by remaining close to vegetation and root structures. Other small peaceful fishes can be their good tank mates and get along with them. Examples are molly, guppy, platy, and zebra danio.
  • Put lots of plants for their habitat. Neon tetras thrive prolifically in this condition. Adult neon tetras may eat their young. We can avoid this scenario if the tank has dense vegetation.

General Rule:

Every linear inch of fish requires one gallon of water.

What is the indicator that your neon tetra is sick or not feeling well?

They must be stressed if you notice that your neon tetras have dull color for several days consecutively.


Females are egg layers. In the wild, they reproduce quickly during the rainy season. There is a trick to breed them successfully. Sparing a dedicated tank for the eggs to be laid and soon will house the new baby neon tetras to grow would be the best strategy. This option will protect the babies.

You can try putting two males and two females in the breeding tank. Let them stay for one to three days. After the waiting period, remove them from the grow-out tank and put them back to the original aquarium.

Final note

A large school of neon tetras showcases a magnificent site within the community freshwater tank. Almost all local pet stores have them in store for you. Their blue lines exhibit a relaxing contrast to your green aquarium garden. Try and witness these vibrant looking fishes swimming in groups in your aquarium!



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