angelfish colors fading

Why Do Angelfish Change Colors?

Aquarium owners love angelfish because they come in a variety of hues. A tank-full can have an assortment of vibrant shades that bring a little more color into your daily life. However, you shouldn’t color-coordinate your aquarium just yet. At any moment, those angelfish might change colors. They do so quite often and for a multitude of reasons.

Angelfish change colors due to age, illness, unhappiness, and stress. They may also jump hues because of aggression, mating behavior, and the brightness of the room they are in. The vertical stripes on an angelfish don’t change color. However, these often appear, reappear, and fade slightly. Changing color is usually perfectly natural.

Angelfish can go for months without changing their colors. Other times, they will change once or twice per day, depending on the circumstances. Sometimes, an angelfish will change its color so subtly that you won’t even notice. It’s only concerning when this is coupled with odd behavior or other physical changes. This can indicate sickness in a fish.

How Can Angelfish Change Color?

Angelfish have chromatophores, which are cells that contain pigments and reflect light. Chromatophores are found in all kinds of animals, including:

  • Reptiles
  • Fish
  • Crustaceans

Chromatophores are responsible for the skin and eye color of cold-blooded creatures. However, angelfish have a little more freedom with their chromatophores. They can change colors willingly.

This comes at a cost. The chromatophores require energy in order to control the hue of the fish on a day to day basis. If the fish is ill, under stress, or malnourished, the resulting lack of energy will show in their colors. This coloring can be regained by sleeping, eating well, and remaining calm.

As such, angelfish colors can serve almost like a mood ring. Want to tell when your fish is in good health? Just take a look at their colors.

When Do Angelfish Change Colors?

Some angelfish will change colors in a matter of minutes. Others have a more gradual alteration. It depends on the fish and their circumstances.

It may be alarming to see a fish going through quick color changes. It can even be anxiety-inducing to see a once vibrant fish slowly turn pale. However, you can identify the reason for the change, be it serious or trivial. Just look for these signs – and their meanings.


When angelfish sleep, they often lose their color. This happens because, like any living organism with tissues and cells, angelfish get microtears all over their brains and muscles as the day goes on. When they sleep, their body can concentrate on regenerating these microtears. This is why so many living organisms need sleep.

When an angelfish is restoring any microtears in the body, this process takes energy. So, instead of using the energy to keep the pigment of the skin vibrant, the color usually becomes dull when the angelfish is sleeping. Once awake, the skin returns to its natural, vibrant self. This process is usually quick and the angelfish does not take long to go from dull to colorful.

It may become difficult to know when exactly angelfish are asleep. They don’t lie down at the bottom of the tank and stay still, as you’d expect. Instead, they enter a sleep-like state where they swim slowly and are generally inactive.

Swimming less is also deliberate. It requires less energy than swimming normally, allowing the angelfish to replenish its energy. Once the angelfish gets its natural color back and seems livelier, it means it has woken up.


The color of an angelfish becomes more intense when they are fighting. They use this tactic to:

  • Establish dominance
  • Frighten their opponent
  • Confuse other the senses of other fish

When something in a fish’s field of view is particularly bright, it catches their eye and makes them wary. It will be unable to concentrate when its entire vision is dominated by overwhelmingly bright colors. So, if you notice that:

  • Your angelfish’s color suddenly becomes bright
  • It is swimming rapidly around other fish

This is usually a sign of aggression. In this case, consider separating the aggressive angelfish from the others.


When an angelfish is hungry or has a poor diet, its color will begin to fade. This usually happens slowly, but you can catch it before the fish gets too unhealthy.

Avoid over-feeding the other fish in the tank by just pouring more fish food into the water. Instead, wait and observe if the angelfish can reach the food before it’s all out. If it cannot, temporarily separate the angelfish in a different tank, so the sickly fish can focus on eating and getting better.

On the flip side, an angelfish’s skin will also become more vibrant to catch your attention because it’s hungry. This change can happen very quickly and it’s usually when people pass by the tank.

do angelfish change color as they age?


Sick angelfish lose their color. This depends on what kind of illness they have and how fast it’s eating away at their life. As such, the color change may happen very quickly or very slowly.

If you are unsure that your fish is sick, observe and see if it has also been behaving strangely. Aside from fading color, you should notice:

  • Unusual swimming patterns
  • A lack of appetite
  • Holes, bulges, or spots
  • Torn fins
  • Protruding or lost scales
  • The angelfish getting attacked by other fish in the tank

A sick fish will not have the energy to maintain its usual cellular operations. This will prevent the body from controlling the hue of the fish. As the body deteriorates, so do the cells and, thus, the chromatophores.

Water Quality

To live a healthy life, angelfish have specific needs for their water. Everything from the pH levels to the water temperature should be in perfect condition. Otherwise, the fish in your tank will get sick and stressed.

How fast will an angelfish’s color change? This depends on how bad the situation is in your tank. The fastest change happens when the oxygen levels are low. The fish will begin swimming to the surface of the water to breathe.


Angelfish wear their heart on their sleeves. It’s easy to tell when something is wrong (or right) because of how their color changes. When stressed, your angelfish will fade in its hues. The more stressed it is, the faster this happens.

  • If it’s caused by aggressive behavior from another fish, the angelfish will pale very quickly.
  • If it’s due to parental stress in pregnant angelfish, the change might happen slower.


Angelfish will fade in color because of physical injuries. It takes a great deal of energy for the cells to regenerate. The body may forgo the cellular procedures responsible for maintaining color and focus on regenerating tissue.

Mating And Breeding

Male angelfish will become very bright in color when trying to impress female angelfish. According to the University of Leiden, cichlids choose their mates based on color. Bright color means the male is:

  • Strong
  • Dominant
  • In good health

In a fight for dominance, a frightened angelfish will try to hide. This is done by fading its colors and blending in with the background. As such, dull colors mean weakness.

Once angelfish choose their mate and are paired, they will continue to have bright coloring. This will intimidate other fish from getting close to their mate or their eggs.


Vivid color in an angelfish indicates good health. This brightening is usually slow, especially if a fish is recovering from an illness.


As an angelfish grows up, it becomes stronger and healthier. This results in more colorful scales. The opposite happens when an angelfish is old. It may not be able to maintain its scales like it used to.

Food Quality

Poor-quality food may lack certain nutrients, making your fish have dimmer colors. After changing the type or brand of fish food, it’s common for the fish to change hues as they adjust. However, if your angelfish’s color seems a bit dull after changing brands, it could be the quality of the food causing the change. All fish need:

  • Fats
  • Fiber
  • Carbs
  • Minerals
  • Protein
  • Vitamins

While some fish foods are rich in one category, they may be lacking in others. This will spell trouble for the health of your fish.


Angelfish are very sensitive to their environment. Because chromatophores absorb light, the brighter the room, the more colorful the angelfish will be. In fact, when asleep, an angelfish’s color will fade faster with the lights off. This change happens relatively quickly because of how light-absorbent chromatophores are.

Is your tank in a busy part of the house? Does the light keep getting turned on and off? Then it’s worth moving the tank to a more secluded area.

In nature, changes in illumination don’t happen as quickly or as often. Changing color is completely natural for angelfish. However, frequent, artificially-induced changes in color can actually be detrimental to the health of your fish.

Why Do the Stripes on Angelfish Fade?

Angelfish fade their stripes so they can blend in with plants and hide from predators. In an aquarium setting, if there are no plants, an angelfish will fade its stripes even more. This will be paired with hiding at the bottom of the tank. It may try to match its stripes to the color of the rocks and sand. It will stay there until it feels the danger has passed.

The more frightened the angelfish is, the more the stripes will fade. Sometimes, the stripes will disappear completely. Of course, this means that the fish is going through unimaginable stress. If this goes on for multiple days, you must intervene before the stress alters the fish’s physical health permanently.

Angelfish Color Meanings

Do certain colors have specific meanings? While it will vary from fish to fish, there are a few generalized meanings. Keep an eye out for these shades, and then compare them to environmental factors. It may help you improve the life of your fish.

Angelfish Turning Yellow

Angelfish may turn yellow depending on their breed. For example, zebra angelfish or silver angelfish may take on a yellow hue when mating, stressed, or even randomly.

However, other kinds of angelfish become yellow due to poor water quality or overcrowding. Be sure to check your tank’s chemical balance and water levels. If there are too many fish in the tank, you may need to separate them.

Angelfish Turning Red

If it’s not an iconic color for its breed, redness in your angelfish is a sign of ammonia poisoning. This isn’t just a change in hue, but actual burns appearing on your fish. The chemical imbalance will eat away at its body and cause discomfort. Be sure to change your water more frequently, and check on the chemical balance.

Angelfish Turning Green

A green hue appearing in your angelfish is a sign of illness. It may indicate that they’ve contracted Velvet Disease, or other sicknesses. When paired with irregular swimming habits and heavy breathing, that’s bad news. Your fish may be nearing a fatal stage in its illness.

Be sure to check out its water quality, including the temperature of the tank, and make corrections. This will help the fish recover.

why do the stripes on angelfish fade?

Angelfish Turning White

Angelfish may turn white due to a lack of oxygen in their tank. This causes their stripes to fade and their brighter colors to dim. This will give them a grey, washed-out look.

You may also find the eggs of your angelfish turning white. This is caused by fungi growing on the exterior of the eggs. If there is a bacterial imbalance in the tank, the protective outer coating will be compromised. A fungus may work its way in and begin to damage the eggs.

Angelfish Turning Orange

If your angelfish suddenly brightens to an orange, especially around the dorsal fins, then good news. You may have a koi angelfish.

It’s common for these breeds to be kept in poor, over-packed conditions in pet stores. This causes them to fade in color, losing their orange hue. When that happens, new owners may buy the fish believing it’s a different breed. Once it has a healthy environment, it will brighten up and reveal its telltale coloring.

Angelfish Turning Black

An explosion of black coloring on your angelfish usually means it’s happy and comfortable. After all, white is more prominent when the stripes fade. The fish may seem blacker when these stripes brighten up again.

If the angelfish has recently been transferred from a pet store or a poorly regulated tank, this is a natural change. It actually proves that your tank is healthy for it.

Angelfish Turning Brown

If your angelfish turns a light brown, then this may be a natural part of its color-changing habits. The black stripes may dull as the fish sleeps and, therefore, appear brown. Light changes may also cause this hue to fade.

However, if your angelfish turns dark brown and maintains this color, that’s bad news. It may have contracted Velvet Disease. This will cause them to grow gold, brown, or green in color.

No matter the case, keep a close eye on your fish. The little changes in its coloring will help you take action against bad effects. It can also help you understand the personality of your angelfish better than before.