Why Is My Neon Tetra Turning White?

If you’ve noticed that one or more of your neon tetras has turned completely white, you’re not alone. This is a common problem among neon tetras and there are several possible causes. 

Sometimes, it’s normal behavior for neon tetras to turn pale or white for a short period of time. This is usually caused by stress and usually isn’t anything to worry about.

However, if the fish doesn’t return to its normal color within a few days, then there may be something wrong and you’ll need to take action.

In this guide, we’ll take a look at the most common reasons why neon tetras turn white and what you can do to help your fish get back to its normal color.

Mechanism of Color Fading In Neon Tetras

The fading of the color in neon tetras is an interesting phenomenon that has been the subject of scientific study for many years.

The purpose of this study is to explore the various factors that contribute to the color fading in these fish.

Sexual selection, camouflage, and UV radiation protection are some of the most important factors that determine the color fading in neon tetras.

Chromatophores are the cells that produce pigment in the fish and they are responsible for the coloring in these fish.

That’s why the fading of color is also determined by the age and health of the fish.

As the fish gets older, the chromatophores lose their strength and fade in color.

Sick or injured fish will also lose their color as a result of the stress on their bodies.

The study of the color fading in neon tetras is important because it helps us to understand the complex mechanisms that control the appearance of these fish.

The knowledge gained from this study can be used to improve the care and welfare of neon tetras.

What Are The Reasons For Neon Tetra Color Fading?

There are a few different reasons your neon tetra might be losing color.

In most cases, it’s nothing to worry about and is just a natural part of their biology.

However, there are some instances where fading color can signify something more serious.

Here are the most common reasons for neon tetras losing color.

Wrong water temperature

The temperature is the main reason neon tetras lose their color and go white.

As you know, neon tetras are tropical fish that prefer warm water.

But when the cold season hits the environment, the water in the tank goes cold too if the heater isn’t working correctly.

So it is essential to keep a close eye on the water parameters and make sure the temperature is stable.

If the water temperature falls below 68 degrees Fahrenheit, you will need to take action to heat the tank.

For example, if you don’t have a heater, buy one to keep the water at a stable temperature.

And always remember, when the water is too cold, it will cause the neon tetras to lose their color and go white.

So make sure you take measures to keep the tank warm and your fish healthy!

Bright Lighting

If you’re looking to keep neon tetras in your aquarium, it’s essential to be aware of maintaining a circadian rhythm.

This means providing 12 to 14 hours per day, with the light turned off automatically after a certain number of hours, is essential because prolonged exposure to high wattages of light can be stressful for these fish, leading to gradual color loss.

So be sure to have an automatic timer set up to make things easy for you and your fish!

Incompatible Tank Mates

If you’re not careful, the wrong tank mates can quickly turn your peaceful fish into a stressed-out mess.

Neon tetras, for example, are peaceful fish that don’t do well when housed with hyperactive or aggressive fish.

When they are kept with larger fish in a community tank, there is a high chance of larger fish bullying them.

Bullying can cause stress and depression even in humans, let alone these tiny creatures!

This stress and depression from bullying can cause them to lose color and become pale and discolored.

So, if you’re thinking of adding neon tetras to your tank, be sure to do your research and choose tank mates that will be compatible with them. Otherwise, you may quickly find yourself with a tank full of stressed-out fish!

Solo Swimming

Neon tetras are social fish that can’t live on their own. You’re doing a terrible thing if you keep them alone without their family.

You’re just making them nervous, sad, discolored, and sometimes forcing them to the brink of death.

Cycling an Aquarium Incorrectly

Aquarium cycling is a critical process to ensure the health and well-being of your fish. However, if it’s not done correctly, it can lead to unpleasant consequences.

Excess ammonia, pollutants, and other waste products can all stress your fish and cause them to change color or even die.

So make sure you cycle your aquarium correctly to avoid any disasters!


In the fish world, the disease is a common occurrence. So, it’s essential to identify the signs and symptoms of neon tetra disease to provide the appropriate treatment.

For example, neon tetra disease is susceptible to various diseases, including Neon Tetra Disease caused by a bacteria called Chloramphenicol.

This bacteria is often found in poorly-maintained tanks and can be deadly to neon tetras.

The first sign of this neon tetra disease is usually a gradual color fading in the fish, and they will start to look pale and may eventually die if left untreated.

If you suspect that your fish have Neon Tetra Disease, it’s important to isolate them from the other fish in the tank and provide them with appropriate treatment.

There is no cure for this neon tetra disease, but there are treatments available that can help prolong the life of your fish.

In general, if you’re having trouble getting your neon tetras to retain their bright color, it might be helpful to look at their environment and remove any potential stressors.

By ensuring your fish are happy and healthy, you’ll be able to enjoy their brilliant colors for years to come!

Why Do Neon Tetras Lose Their Color While Resting?

Have you ever noticed that your neon tetras lose their bright colors when they’re resting? 

It’s a common occurrence, but what’s going on here?

Chromatophores, the cells that produce pigment in fish, require a certain energy level to give color out. So, when you see them resting or sleeping, they are basically saving energy or using the power elsewhere.

That’s why the color fading or discoloration during their resting period is because of their energy-saving mode.

Color is secondary when neon tetra uses its energy to do something else or nothing at all.

So, it is quite normal and okay when you see them changing color while they rest.

Do All Neon Tetras Lose Color At Night?

That’s a question many fish enthusiasts have. The answer is no – the color fading mechanism in neon tetras varies according to the sleeping time, levels of rest, and also on each fish.

For example, some neon tetras may completely lose their color at night, while others may only have their colors fade a little bit.

It all depends on the individual fish and its natural tendencies.

Treatment For Color Fading Of Neon Tetra

Reversing neon tetra’s color loss is straightforward since the fading is usually only a temporary issue.

Provide Your Fish With The Right Water Temperature

The water temperature is the most important factor in keeping your neon tetra’s color bright.

Ensure the water is between 72 to 76 degrees Fahrenheit (22.2 – 24.4 degrees Celsius) to keep them healthy and looking their best.

We recommend getting a tank heater to ensure the water temperature is always within the correct range.

Dim The Neon Tetra Tank Light

When it comes to the neon tetra, you want to ensure that you are providing them with the right amount of light.

Too much or too little can be detrimental to their health and well-being. So, what is the right amount of light for these fish?

Ideally, you will want to dim the tank light in the neon tetra tank, which can be done with a simple light dimmer switch.

By doing this, you will be providing them with the right amount of light – not too much and not too little.

Separate Infected Inhabitants

Because the illness may be contagious, you must quarantine ill neon tetras to prevent having a tank full of afflicted fish.

Avoid Purchasing Sick Fish

When purchasing a new fish for your aquarium, it is essential to be careful and do your research.

One thing to look out for is sick fish. Avoid buying any fish from a breeder that doesn’t have any background information or papers.

It is also important to keep in touch with well-reputed breeders and only purchase fish after a full health check.

This will help ensure that you don’t introduce any sick fish into your aquarium and that your other fish remain healthy.

Quarantine Your New Fish

Quarantine is the process of isolating new fish from your main tank to check for signs of illness.

This is necessary, especially if you’re picking up fish from a breeder or pet store.

It’s important to keep a separate quarantine tank, as it allows you to observe the new fish for any signs of illness without risking the health of your other fish.

If you notice any neon tetra disease symptoms, such as loss of appetite, lethargy, or fin rot, you can treat the fish in the quarantine tank before adding them to your main tank.

Prevention is always better than cure, so make sure to quarantine your new fish before adding them to your aquarium.

Maintain Good Water Quality

One of the most important things to remember when caring for neon tetras is maintaining good water quality.

This can be done by using a canister or hang-on filter, which will help keep the water clean and healthy for your fish.

Get The Foods From Respected Source

Giving your neon tetras the right food is essential to their health and well-being. Make sure to only provide them with food from a reputable brand and source.

Foods like flake food, freeze-dried bloodworms, and tubifex worms are all ideal for neon tetras.

Do Not Overfeed

It is important not to overfeed your fish, as this can lead to poor water quality and health problems.

When you’re feeding your neon tetras, only give them what they can eat within a few minutes.

If there is food leftover after a few minutes, remove it from the tank. This will help keep the water clean and healthy and prevent your fish from becoming overweight.

Monitor For neon tetra disease

If you are a fish keeper and have neon tetra in your tank, you will soon face the problem of neon tetra disease.

Spotting any neon tetra disease in neon tetra fish is not rocket science. It is pretty simple if you know what to look at.

Here are some signs that your neon tetra is sick.

  • Restlessness.
  • Fish begin to lose coloration, often in one part of the body.
  • As cysts in the muscles develop, the body may become lumpy.
  • Fish have difficulty swimming.
  • In advanced cases, the spine may become curved.
  • Secondary infections such as fin rot and bloating.


Do Neon Tetras Glow In The Dark?

No, neon tetras do not glow in the dark. However, their iridescent blue color may give the appearance of glowing.

Why Are My Neon Tetras Staying At The Bottom Of The Tank?

One of the symptoms that neon tetras show when they are sick is staying at the bottom of the tank.

If you see them dwelling on the bottom and staying there for a long time, look closely for other signs and symptoms.

Your neon tetra may be infected and on the verge of contagious to other tank mates. Separate them quickly and treat them properly.

Last Word

Fading colors are quite typical among neon tetras; the reasons are usually straightforward.

However, it might take a little detective work to ascertain whether poor diet, water conditions, or infection are the root causes.

With a bit of care and attention, your neon tetras should remain healthy and beautiful for months.

We hope you have enjoyed this article as much as we did. If you still have any questions, please leave a comment below.