Why Is My Goldfish Turning Black? [Reasons & Solutions]

Why Is My Goldfish Turning Black? [Reasons & Solutions]


Fishes are the most common pets in houses. And many people liked to decorate their houses with fishes because fishes look very beautiful.

Same where goldfishes are one of these fishes which people used to decorate houses and place the Goldfish in a water tank that looks very beautiful.

Goldfishes look very beautiful and the color looks attractive. In the same way, you also took care of your fish like giving food on time, changing the water in the tank, and preventing them from diseases.

Sometimes, Goldfish suffer from diseases like ammonia burn and digestive problems due to which they start to lose colors and turn black which looks very bad.

And you worried about this disease of turning their color black then you should read this article. That’s why we write this article to solve your problems.

And answer your question”Why is my Goldfish black?” Because due to this your goldfish can die also because sometimes it is harmful. And can damage the digestive system and eyes of your fish.

Why Is My Goldfish Turning Black? [Reasons]

why is my goldfish black

1) Because Of Illness
2) Due To Genetics
3) Water Temperature
4) Due To Black In Tank

1) Because Of Illness

1) Because Of Illness - why do goldfish turn black

There are many diseases that are found in the fishes due to dirty water, parasites, ammonia, and water temperature. Many damages occur due to Illness

Sometimes, these diseases change the color of goldfishes. One of the most common diseases due to which Goldfish turns black is ammonia burn and it is very harmful to goldfish.

This disease occurs due to the high amount of ammonia in water that causes ammonia to burn in the body of fishes and they lose their beautiful color and turn black.

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Mainly, fins and gills turn black due to this disease. You can cure this disease by consulting with an expert fish keeper. This disease is also harmful to the fishes.

This disease can damage the eyes of the Goldfish and stomach of the fish due to which they stop eating and get stress.

2) Due To Genetics

2) Due To Genetics - goldfish black fins

There are different classes of goldfishes found in our world. Every class has different specifications, qualities, and abilities. That is changed in every class of the goldfish.

In some classes of goldfishes have the ability to change color with the passage of time due to which Goldfish Turning Black at a stage of their life.

You don’t need to worry about it if it’s due to Genetics because it is not harmful to them and they spend a normal life with normal activities.

The color-changing of goldfish due to Genetics is forever and not changed again and again. In this case, you can purchase a new one and replace it with another.

But on the other hand, black fishes also look very beautiful but before purchasing a goldfish you must find a class that can not change color.

3) Water Temperature

3) Water Temperature - my goldfish is turning black

A change in water temperature is also harmful to goldfishes because temperature matters a lot. Due to water temperature fish suffer from many diseases.

Sometimes, due to the high amount of ammonia in water can damage the color of the Goldfish which turns into black. This will cause the black spots on the body of fish.

Related Post: Why Is My Goldfish Turning White?

Due to temperature many parts of the Goldfish turn black like fins, gills, and dots on the body. When you see goldfish black fins then you just know that the water has a high amount of ammonia.

By preventing this disease you should change the water of the tank regularly with low amounts of ammonia to take care of the Goldfish.

Sometimes, the water has parasites and dirt the water which is harmful to goldfishes so keep an eye on your fish and change the water.

4) Due To Black In Tank

4) Due To Black In Tank - why did my fish turn black and die

Might be possible, where you placed the tank of your goldfish there are black decorations in the background. Because the goldfish changed the color of the skin with black.

Due to the black in decoration, the Goldfish merge its color into the black by seeing the black color in back and mainly change the color of gills.

So, try to remove black things around the tank of the fish to prevent it from changing color. If your goldfish turns black due to this reason then you should not worry about this.

Because when you remove the black things from the background then your goldfish comes into its previous condition within a few days.

It is not harmful to the goldfish because it’s just due to the change of environment. You can cure this by removing black things.

Solutions To This Problem

Solutions To This Problem

We are giving some solutions to this problem.

  • Always keep your fish in a healthy environment.
  • Change the water of the tank regularly.
  • Keep an eye on the fish whether it is fine or not.
  • Check the amount of ammonia in the water.
  • Observe your fish whether it suffers from a disease or not.
  • Give the proper food to your goldfish.
  • Remove the extra food from water urgently.
  • Don’t give more food to your goldfish because overfeeding produces many kinds of diseases.
  • Don’t place black things around the tank of your Goldfish.
  • Place your fish in a big tank.
  • Always use clean water in the tank of the goldfish.

Goldfish Turning Black (FAQs)

Frequently Asked Questions

1) Are goldfish supposed to turn black?

In some classes of fishes, they changed their color due to genetics. And it is not harmful to goldfishes because they changed color and also cured with the passage of time.

In this case, mainly the color of the gills and fins turns black. As well as due to ammonia burn goldfish turn black.

2) How do you treat black spots on goldfish?

By changing the water of the tank, remove the extra food from the tank, and continue the treatment of the fish. You can also consult with a fish keeper to prevent them from this disease.

Anyways parietal now used to treat black spots on the fish. As well as by consulting with fishkeepers you can cure the black spots on fish.

3) Does black spot disease kill fish?

It is good for you to know that this can not be harmful to fish. In the case of ammonia burn then this will kill the fish because it is a very harmful disease.

It can damage the inhalation process of goldfishes because ammonia enters the body from the gills and fins. So, it can damage the process of inhalation.

4) Can goldfish recover from ammonia poisoning?

There is no treatment yet produced to cure ammonia. Otherwise, it will be recovered by preventing changes in the water and changing the tank with a new one.

If the cause is of low effects then it can be cured but if it has effects more than it can not be cured and can damage the eyes of goldfish which results blind. And cannot see things again.

5) How do you know when a fish is about to die?

When your fish is about to die then white spots occur on the body of the fish and the food is uneating. The fish is on the lower surface of the water tank and the eyes of the fish look pure white.

If these symptoms are showing then your fish is about to die. However, the main thing you can easily know whether your fish is living or not is the food which remains uneaten.

6) Why do goldfish turn black?

Due to many reasons goldfish turning black like ammonia burn, water temperature, genetics, and black things around the tank.

These are the common reasons due to which the goldfish turns black. Goldfishes are very sensitive and turn black due to the increase in the amount of ammonia in the water.

7) Why did my fish turn black and die?

If your fish turn black and die then the reason is it is suffering from the disease of ammonia burn which is very harmful to them.

This causes irritation due to which they don’t eat something and have difficulty in the inhalation process. This is one of the killing diseases which can not be cured only if it has no more effects.


conclusionThe experts of Your Aquarium Guide gives you an article due to which you can get the answers to your questions (Why is my goldfish turning black? Why is my goldfish black? Why do goldfish turn black?)

We give the answers to all your questions. If you have a goldfish and are worried about this disease of fish then you should read this article to cure your fish and prevent it from any other disease in the future. Because the fishes need to care about their food and especially water.

With this, you also consult with a fishkeeper because they know more about fishes and where you need help Your Aquarium Guide is always here to give you the right way to keep your pets healthy.

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