Do Cardinal Tetras Change Color?

Cardinal tetras are undoubtedly beautiful fish with their fantastic color and pattern. They are active fish that most owners enjoy watching when they swim around. These fish have unique characteristics like swimming in schools, living in various environmental conditions, and surviving in the least aquarium equipment. But some people also wonder if Cardinal tetras change color or not?

Cardinal tetras change their color depending on what mood it is feeling at that moment. For example, some fish change their color when they are ill, stressed, or threatened. While color-changing might also indicate aging, hiding for predators, or change in their usual water parameters.

However, whatever be the reasons, we will discuss all of them in this article to give you a closure look at the life and behavior of Cardinal tetras. I hope it helps you in fish keeping.

How Do Cardinal Tetras Look Like?

Cardinal tetras are small, peaceful fish that can grow to be around two inches long. Their coloring is gorgeous and makes these fish stand out against other tropical aquarium plants and fish.

Cardinal tetras have an orange-red body with thin, black horizontal stripes running from behind its head to its tail. Cardinal tetras have a bright and colorful body with unique red/orange and blue colors. They have a unique and eye-catching look, which is why these fish are so popular in the aquarium hobby.

What Is Camouflage?

Cardinal tetras are from the Amazonian environment. They have an incredible camouflage ability, their unique capacity for disguising themselves against different types of backdrops and backgrounds.

Cardinal tetras use this skill to easily avoid predators or catch prey by blending into certain environmental conditions like plants, rocks, gravel, etc. In addition, they can change their color depending on their surroundings, which makes them so interesting to keep in the aquarium hobby.

Do Cardinal Tetras Change Color?

Yes, Cardinal Tetras do change color. Camouflage is a common defense mechanism Cardinal Tetras will use to protect themselves from predators. Cardinal Tetras are a schooling species of fish, so they often exhibit this behavior when more than one individual is in the tank.

These tetras change color as part of their daily routine, and it’s not anything significant that can’t be easily missed by those who aren’t looking for it. They may do so to blend in with their environment, and you can even see changing colors when they get excited or stressed out, such as during feeding time.

In addition to this, Cardinal Tetras also have a particular way of communicating through different colors. So if you notice your fish has changed its color, take a closer look to determine what it is trying to communicate.

Why Do Cardinal Tetras Change Their Color?

Cardinal Tetras are sometimes considered one of the most beautiful freshwater fish in the world. Cardinal tetra is a trendy pet because it is small and non-aggressive to other fish. In addition, they are present in different colors, making them exceptional for aquarists who love collecting rare fish species.

Here’s what you need to know: Cardinal Tetras change color because of the following reasons.

Overexposure To Sunlight Cause Cardinal Tetras To Change Color

Cardinal Tetras change color when you expose them to sunlight for an extended period. These tetras have cells under their skin called chromatophores which contain red, yellow, and orange pigments.

When Cardinal Tetra faces direct sunlight, these colors in the chromatophore expand. As a result, it appears bright with few light stripes. However, Cardinal Tetra gets back to its original color when it is taken away from sunlight and placed in a shaded area for some time.

Cardinal Tetra Color Change Is Related To Their Health

Healthy Cardinal tetras have vibrant colors. However, there are two reasons why Cardinal Tetra changes color when it is sick:

When a fish does not eat, the chromatophores in its skin lose color. Therefore, Cardinal Tetras become pale when it loses its appetite, which is very common in Cardinal tetra diseases like fin rot.

When parasitic or bacterial infections are on Cardinal Tetras, their scales start to separate due to the damage. Therefore, it is a dangerous Cardinal tetra illness that often causes death in Cardinal tetras if not treated immediately.

Cardinal Tetras Change Color Due To Change In Water Parameters

Cardinal tetras change color due to the change in water parameters like pH and temperature. Therefore, Cardinal Tetra becomes pale when placed into a new environment with different pH or temperature than its previous habitat.

When you expose cardinal tetra to warmer water, it starts getting red pigmentation on its skin because of exposure to sunlight. It is due to Cardinal Tetra’s attempt to absorb more sunlight because of the warmer water. However, when you place Cardinal tetras in cold water, this fish gets bluish color. It is a sign that they are not well and need proper care from their owners.

Cardinal Tetras Change Color When They Need To Hide From Predators

Cardinal Tetras change color when they need to hide from predators. This fish changes its colors to match the environment where it is hiding so Cardinal tetra can avoid being noticed by potential Cardinal Tetra predators.

Once Cardinal Tetra gets frightened, this fish immediately hides in rocks or plants and quickly camouflages itself with its surroundings, making it difficult for its predators to find them. These tetras change color rapidly with this type of Cardinal Tetra camouflage known as “passing-shade,” which allows Cardinal tetra to blend in the environment where it is hiding.

Cardinal Tetras Change Colors To Communicate With Other Cardinal Tetras

They change color to communicate with other Cardinal tetras. It is a type of nonverbal communication where Cardinal Tetra uses colors as signals for mating, defending their territory from intruders, and warning others about the danger around them.

This form of Cardinal Tetra communication happens during Cardinal tetra spawning when Cardinal Tetra wants to attract Cardinal tetras for mating.

Is It Normal For Cardinal Tetras To Change Their Color After A Certain Age?

Cardinal Tetras are known for being able to change their coloration after they have grown up. It is normal, although not all Cardinal Tetra fish will do this. For example, aquarists have observed that the Cardinal Tetras, who start with a red or orange tint, will slowly turn blue as they get older.

Cardinal Tetras, born with black or dark blue color, will usually keep this color as they age. However, like most other tropical fish, Cardinal Tetra fish can change their colors to suit their surroundings and moods.

Moreover, you will also notice fading or less vibrant coloration with age if you provide Cardinal Tetras with the right conditions for them to thrive. For example, if there is a lack of plants and hiding spaces, Cardinal Tetra fish may lose their bright colors because an environment that does not suit their needs will stress them out.

Does Cardinal Tetra Coloration Change After Breeding?

Fish do not typically experience any color change after breeding. For example, Cardinal tetras can be bred, producing a few hundred fry each month for several months before they become too weak to breed any longer. As they grow more vulnerable, their vibrant color fades and becomes dull.

Cardinal tetras are one of the most vibrant fish available. They are not like bettas, which will turn pale after they breed. However, their coloration can get brighter during breeding if you feed them well and clean their environment.


In conclusion, Cardinal Tetras are a very popular type of freshwater fish. They are beautiful fish to have in your home aquarium, thanks to their colorful body.

However, there is no definite answer to whether Cardinal Tetras change color. It depends on the Cardinal Tetra itself and other factors such as temperature, mood, stress levels, etc. But, even though they change color, Cardinal Tetras do not alter their scales’ color completely as some fish can do.

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