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Why Your Parrot Fish Is Turning Black And How To Stop It!

Although parrot fish are a niche species kept within the fish keeping community, they have been slowly increasing in popularity with people new to the marine side of the hobby.

We would usually not recommend that someone new to the fish keeping hobby keeps a parrot fish in their tank due to it being challenging to maintain their strict dietary needs.

Still, we have noticed a number of people reaching out about their parrot fish turning black recently and we wanted to publish this article to help our readers identity and correct the problem with their fish.

As we literally just mentioned though, maintaining the correct diet for a parrot fish is a challenge and issues with the diet of your parrot fish can actually be one of the more common reasons that it will start to turn black but we will cover this in more detail below.

Is It Normal For A Parrot Fish To Turn Black?

The only normal and natural reason that a parrot fish will start to turn black is due to its pigmentation coming in late.

A baby parrot fish is not always the same color it will be once it reaches adulthood so as it grows, its pigments can change often causing it to have black parts form on the fish.

All other causes of black spots on a parrot fish is often a sign of a potential problem. Some of these problems can be serious where as other potential problems are relatively easy to correct and you should be able to have your parrot fish back to its normal color within weeks.

What Causes A Parrot Fish To Turn Black?

There are usually nine main reasons that a parrot fish will start to turn black and depending on the specific setup of your aquarium, some can be more common for you than others where as the causes in your tank may be rare for someone with a different setup.

Due to this, we have just organised the causes of a parrot fish turning black in a generic order below. Although we have tried to keep them in an order where the more common causes are towards the top, this can change for each aquarium setup.

Old Age Setting In!

When a parrot fish gets towards the end of its life and old age is taking its toll, the fish can start to develop black spots. This is a very common cause of black spots on parrot fish and unfortunately, it is not something that you can fix or change.

Thankfully, this is often due to issues with the pigment in the fish rather than anything serious and in most cases, it really shouldn’t cause any problems with the lifespan of your pet parrot fish.

Natural Pigmentation!

As we touched on earlier in the article, a baby parrot fish is not always the same color as it will be once it is an adult. As your parrot fish reaches the juvenile stage of its life, it can start to develop its adult pigments with the black parts starting to form seemingly out of the blue.

This is normal and very common with parrot fish and it is nothing to worry about and is totally natural for the species.

Problems With Their Diet!

A parrot fish has very specific dietary requirements which can often be hard to maintain in an aquarium, especially if you are new to keeping parrot fish. They are known as herbivores and their diet revolves around eating algae, plants, and other similar food sources which can often be hard to recreate in an aquarium setting.

If your parrot fish is not getting the correct diet, it can start to develop black spots on its body. This is one of the more common reasons that parrot fish start to turn black and thankfully, it is something that you can easily correct.

The first step in correcting this problem is identifying what food sources your parrot fish is missing from its diet. You can do this by researching the specific dietary requirements of parrot fish or by speaking to a vet or experienced parrot fish keeper.

Once you have identified the food sources that your parrot fish is missing, you can start to look at adding them to its diet. This can be done in a number of ways but the most common method is by adding supplements to their food which will provide them with the nutrients they are missing.

You can also look at changing the type of food you are feeding your parrot fish to something that is closer to their natural diet. There are a number of specialist parrot fish foods available which contain all of the nutrients they need to stay healthy but they can be difficult to find and are often expensive.

External Parasites!

Another common reason that parrot fish start to turn black is due to an infestation of external parasites. These parasites will attach themselves to the skin of your parrot fish and feed off their blood which can often lead to anemia.

Anemia is a condition where there is not enough oxygen being carried around the body by the red blood cells and it can often lead to the fish turning black as the oxygen is not able to reach the cells in their body.

External parasites are often difficult to spot but there are a few signs that you can look out for which may indicate that your parrot fish has them. These include:

  • Black spots on the skin.
  • The fish scratching itself against objects in the tank.
  • The fish appearing to be lethargic or listless.

Some external parasites are actually black too often giving the illusion that your parrot fish is turning black when it is just the parasite taking hold. Still, even if the color change is just due to the parasite, it still needs to be dealt with quickly.

Stress And Anxiety!

Like all animals, parrot fish can suffer from stress and anxiety which can often manifest itself in a number of ways. In some cases, this can mean that stress manifests itself in parrot fish is by them turning black.

When a parrot fish is stressed or anxious, it will release a hormone called cortisol into its bloodstream. This hormone is designed to help the fish deal with stress but it also has a number of side effects which can include turning the parrot fish black in some rare cases.

Poor Water Quality!

One of the most common reasons that parrot fish turn black is due to poor water quality. Parrot fish are very sensitive to changes in their environment and even small changes in water quality can have a big impact on their health.

There are a number of different factors which can contribute to poor water quality but the most common include:

  • Ammonia levels that are too high.
  • Nitrite levels that are too high.
  • Nitrate levels that are too high.
  • A lack of oxygen in the water.
  • Too much CO2 in the water.

If you suspect that poor water quality is the reason your parrot fish is turning black, the first thing you need to do is test the water. You can do this yourself with a home test kit or you can take a sample of the water to your local fish store and they will be able to test it for you.

Once you know what the problem is, you can then start to look at correcting it. This may involve making some changes to the way you clean your tank or it could mean changing the type of filter you are using.

It is also worth mentioning that parrot fish are very sensitive to changes in their environment and even small changes can have a big impact on their health. If you are making any changes to your parrot fish’s tank, make sure you do it slowly and gradually to give them time to adjust.

Black Spot Disease!

One of the most common diseases that parrot fish can suffer from is black spot disease. This is a parasitic infection which is caused by a single-celled organism called Ichthyophthirius multifiliis.

This parasite invades the skin of the parrot fish and causes black spots to appear on their body. The parasite then feeds on the blood of the parrot fish which can often lead to anemia.

Anemia is a condition where there is not enough oxygen being carried around the body by the red blood cells and it can often lead to the fish turning black as the oxygen is not able to reach the cells in their body.

Black spot disease is very contagious and it can spread very quickly through a tank. If you think your parrot fish has black spot disease, the best thing to do is to isolate them from the other fish in your tank.

You should then treat the tank with a medication which is designed to kill the parasites. It is important to follow the instructions carefully and make sure you remove any carbon from your filter before you start treatment as this can remove the medication from the water.

Once the parasites have been killed, you will then need to treat the tank with a de-wormer to make sure all the parasites are removed from your parrot fish’s body.

Necrotic Skin!

If your parrot fish ends up getting injured there is a small chance that the skin around the wound may turn necrotic. Necrotic skin is dead skin and it will often turn black in color.

This can be hit and miss for your fish as in some cases, necrotic skin will just peel off your fish but in other cases, it can start to spread and once it starts spreading, it can be difficult to stop.

Fungal Infections!

Fungal infections are another possibility if your parrot fish turns black. These are usually caused by a fungus called Saprolegnia and it can often cause the skin to turn black or gray in color.

Fungal infections are most commonly found in fish that have already been injured or that have compromised immune systems. However, they can also affect healthy fish if the water quality is poor.

If you think your parrot fish has a fungal infection, the best thing to do is to treat them with an anti-fungal medication. It is important to follow the instructions carefully and make sure you remove any carbon from your filter before you start treatment as this can remove the medication from the water.

You should also make sure you keep a close eye on the fish and if the infection does not seem to be improving, or if it starts to spread, you should take them to your local vet for further treatment.

Summary Of Causes Of Parrot Fish Black Spots

Here is a quick re-cap of the points that we covered above that can cause a parrot fish to start turning black:-

  • Old Age Setting In!
  • Natural Pigmentation!
  • External Parasites!
  • Problems With Their Diet!
  • Stress And Anxiety!
  • Poor Water Quality!
  • Black Spot Disease!
  • Necrotic Skin!
  • Fungal Infections!