Why Do Clownfish Have Black Spots?

Do you have a Clownfish in your aquarium? Do you like their vibrant appearance? We know you do. Clownfish are brightly colored fish found in the open ocean. 

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Besides bright colors, they have black spots on their bodies. This colored spectrum gives them their clown-like appearance. And no wonder why we call them “Clownfish.” 

But being a pet owner, you might think a lot about the black spot on their bodies. Why do Clownfish have black spots? Is it harmful to them, or is it beneficial for them? 

In this article, you will find all of the answers to these questions. You will get to know a lot more about your favorite pets’ nature. So let’s not delay more. Start to read up.

Why Do Clownfish Have Black Spots?

Clownfish have black spots on their bodies for several reasons. However, the spots are actually dark pigments that help Clownfish camouflage themselves in their surroundings. 

The clownfish and anemone have a symbiotic relationship. The clownfish lives in the anemone’s mouth, usually located on the top of a rock or coral reef. The anemone’s stinging tentacles constantly flow water over the clownfish so it will be able to breathe. 

The anemone also protects from potential predators. But when there is no anemone present, Clownfish used to reside by corals. And that’s when coral stings them with black spots. 

However, to be entirely mixed up with an anemone, a black spot on a clown fish’s body helps a lot. Also, Clownfish use these spots to frighten away predators and attract prey.

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What Causes the Black Spots on Clownfish?

Clownfish are popular aquarium fish, and they come in a variety of colors, excluding only orange. But the asymmetric black spots on clownfish may be common in any color. 

Researchers have found that exposure to coral causes hypermineralization in Clown fish’s bodies. This hypermineralization further leads to the appearance of black spots on clownfish skin. 

Clownfish are especially sensitive to changes in their environment. But apart from the natural marine environment, if you see significant black spots on your clowns, there might be changes in water parameters. 

And a bacterial or parasitic attack can also be a cause behind abnormal black spots on clownfish. 

How Do Clownfish Use Their Black Spots?

Clownfish are masters of camouflage. They use their black spots to disguise themselves from predators and prey. During the day, they swim around in groups, and at night, they hide under rocks or coral reefs. 

Clownfish are carnivores, eating mostly small crustaceans and worms. They also eat smaller fish and jellyfish and will even eat algae. Clownfish have a few predators, including birds that can sometimes steal their eggs. 

Other attacks include sharks and moray eels. Clownfish are able to change their colors based on whether they are in a hot or cold environment. 

For example, when it is hot and humid, the Clown Fish’s skin will become a dark red color, but if it is cold and dry, their skin will turn blue-green. 

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Do All Clownfish Have Black Spots? 

Though it’s quite normal that clownfish will have black spots. And many people assume the same. But this may not always be right. 

In fact, some clown fish varieties do not have any black spots at all on the primary level! With time, environmental effects cause these colorful fish to have dark markings on their bodies. 

Scientists believe that it may do with displaying dominance or attracting a mate. Most Clownfish, including the popular Ocellaris Clownfish, have black spots on their bodies. 

However, a new study shows that not all clownfish have these spots and that some species lack any markings! 

The study was conducted by researchers in the Philippines who collected more than 100 clownfish specimens from different parts of the country. 

They used a combination of morphological and genetic methods to determine whether or not clownfish had black spots. Surprisingly, only about half of the specimens tested had them.

How to Prevent Clownfish from Getting Black Spots?

If your clownfish have black spots more than natural, then there might be a parasite called Paravortex turbellaria flatworms that is causing it. 

A regular formalin bath will help a lot in that case. You can also quarantine your clownfish for a few days to recover quickly and avoid more infection. 

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However, if your fish do not get the proper nutrients, they can develop black spots on their skin. To prevent this from happening, keep your clownfish well-fed and healthy. 

Please provide them with a warm and clean environment. Constant water change is also helpful. Lastly, a solution called Prazipro is also helpful against flatworms, turbellarians, flukes, and others. 


Clownfish have black spots to help them camouflage in their coral reef habitat. The black spots help break up the fish’s outline and make it harder for predators to detect them. 

Clownfish also use their bright colors to communicate with each other and attract mates. But when you notice abnormal growth of the black spots on your Clownfish, don’t wait to get your fish treated. 

Simple water changes and quarantine at the right time may help a lot. Besides that, give your beautiful clownfish good food and clean surroundings to live a happy and healthy life.

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