Why is my Betta Fish Progressively Losing its Color?

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Loss of coloration is a common symptom of illness in aquarium fish.

A Betta fish that’s progressively losing its color and is not interested in swimming may signal just that.

Fading pigmentation could be a bad sign for fish, especially if combined with lethargy and a lack of appetite.

Can the fish get better and regain its vibrancy?

Could the Betta lose its color and turn all white naturally?

Why is Your Betta Fish Losing Its Pigmentation?

Some varieties of Betta fish are extremely colorful and in most cases, a specimen will not lose its colors naturally. In my experience, the pigmentation intensities of a fish are an indicator of its well-being, and many experts agree with that.

Here’s why your Betta fish may be progressively losing its body color:

Your Betta fish is likely losing its bright colors due to a stressful environment. Stress in aquarium fish can be the result of foul water conditions, sudden changes in water parameters, or aggressive tank mates. The fading colors can be restored once measures to resolve the underlying issues are taken.

The same Betta before and after losing its color due to stress

By Schmohawk17

When a Betta fish loses its coloration naturally it’s most often due to a Marble gene.

Fish with the gene may randomly change their entire color patterns. However, if the loss of color is accompanied by other symptoms such as lethargy, a lack of appetite, or bloating you should likely take immediate action.

With that being said, it’s time to see how each factor can cause a betta fish to turn white, in more detail:

1. The water’s parameters are off and the fish tank needs cycling.

If an aquarium has not been properly cycled, the water inside could end up poisoning the Betta fish.

This typically happens if you add fish to a tank too soon or if you sprinkle more food than the fish can eat in 3 minutes (also called “overfeeding”).

The symptoms of poisoning from water pollution manifests as lethargic behavior and a simultaneous loss of color throughout the whole body of the fish. Affected Betta fish could turn completely white and are also likely to refuse eating or swimming.

These symptoms may sometimes be accompanied by reddened gills that move rapidly. “Cycling” refers to having an established nitrogen cycle in the fish tank through the help of beneficial bacteria.

Beneficial bacteria will convert the toxic Ammonia and Nitrite that aquarium fish produce into less harmful substances. Here’s how the water parameters of a cycled aquarium look like, measured in Parts per Million:

  • 0 PPM of Ammonia;
  • 0 PPM of Nitrites;
  • 10 to 15 PPM of Nitrates.
a diagram of the Nitrogen cycle in an aquarium

Ammonia and Nitrites are severely toxic to all freshwater fish and should remain at levels of 0 ppm at all times.

Anything above 20 ppm of Nitrate for a prolonged period of time may also cause damage to your Betta. If the aquarium parameters where your pale Betta fish lives are not within these ranges you’ll need to further cycle the tank.

Test the water and make an assessment. There is more than one way to do that, but I recommend using a liquid water test kit, such as API’s Master Test Kit which you can check at Amazon.

In fact, water test kits are an essential accessory for any fish tank. I prefer the liquid kit because, in my experience, water test strips are notoriously inaccurate.

You could also bring a small sample of your aquarium water to a local fish store and they will test it for you.

Mind that you’ll need to specifically ask about each water parameter, or you’ll receive an “it’s good” kind of answer.

Anyhow, if it turns out that the Betta’s fish tank has its Ammonia or Nitrite levels elevated, you’ll want to perform a partial water change. Change no more than 30% of the aquarium’s water to physically remove part of the Ammonia or other toxins without causing more stress to the fish.

You can then proceed by adding good bacteria to the aquarium, which will prevent future Ammonia and Nitrite spikes when established.

I have reviewed a couple of reputable bacteria supplements here but something like Tetra SafeStart should likely do the job. Note that the beneficial bacteria could establish themselves on their own, but that often takes more than a month, and if your Betta is suffering from poisoning, you may not want to wait that long.

With the addition of bottled bacteria, you’re looking forward to a fully cycled aquarium in less than 2 weeks.

Keep testing and remove more water if needed, but do wait for 2 to 3 hours before each water change.

What’s important to remember here is that a cycled aquarium does not mean less maintenance.

The beneficial bacteria will convert Ammonia and Nitrite to Nitrates, which are not as toxic to fish in the short run, true. However, Nitrates will accumulate and still need to be exported from the aquarium through partial water changes.

Author’s note: High Nitrates in a fish tank can also cause the outbreak of invasive algae species and the appearance of unsightly worms which may or may not be dangerous to the fish inside.

Anyway, Betta fish are often kept in small tanks, and contrary to what a beginner may feel, smaller fish tanks require more maintenance than larger ones.

This is because a small change in the water parameters is immediately felt throughout the whole aquarium.

Betta fish are best kept in tanks that are over 3 gallons in water capacity, which provides a safer environment for the pet. If your Betta’s tank holds less than 3 gallons of water, you’ll likely need to choose a more appropriate one for the benefit of the fish.

2. There were temperature fluctuations during the night.

Betta fish, like most other aquarium fish, are extremely susceptible to stress by temperature fluctuations. A drop of 2 to 3 degrees at night could be enough to send a Betta fish in shock.

The affected specimen usually displays a paleness or a complete loss of body and fin color. Lying sideways on the bottom and lack of motivation to swim are behavioral signs of a fish that has gone through thermal shock.

close up of an aquarium thermometer

By BrittanyWinchester

In my experience, water temperature fluctuations are one of the most overlooked reasons for a Betta fish that has inexplicably fallen ill.

The thing is that when in shock, the fish has a compromised immune system and becomes vulnerable to all kinds of diseases, including dangerous external parasites such as the ones causing Ich. It’s no surprise that I’d see a significant increase in reports of Betta illnesses during the Spring months.

Spring is when temperatures fluctuate the most between day and night, on average.

In fact, this is the most common reason why pet parents who take care of their fish by the book still witness unexplained fish illness.

I know it took ME some time to realize what was happening…

Investing in a good aquarium heater is underestimated in this hobby.

Having a reliable, self-adjusting heater is likely the best way to prevent all of this and maintain stable water temperature in a Betta aquarium.

As with most other cases, soon after things normalize the fish will regain its bright colors.

Related: Aquanswers’ Top Heater Picks for Small Betta Aquariums

3. You changed more than a third of the aquarium’s water at once.

Though water changes are needed for the proper maintenance of an aquarium, it could be that you’re overdoing it. Click the link for a deep-dive into the topic as I’ll just summarize it below.

Changing large portions of aquarium water removes accumulated ions such as Nitrates.

When you remove nearly half of the total Nitrate ions you’re interrupting the osmotic balance between the fish’s body and the water it lives in. The Betta may then experience impaired fluid retention which results in its internal organs swelling. This situation could in turn lead to a suppressed swim bladder, the organ responsible for buoyancy in fish.

The Betta could end up with its belly up and swimming upside-down, which is often accompanied by a fading body pigmentation. To avoid all of this, you can simply perform smaller, more frequent water changes.

Change no more than 15% of the water at a time.

What I like doing is changing 15% of the water in the morning before going to work and then another 15% right after I get home in the evening.

This gives my Betta enough time to gradually adjust to ion contents and I still maintain a clean fish tank.

Also, always make sure that the water you use for the exchange matches the aquarium’s one in temperature.

4. There was a fluctuation in the water’s pH.

Betta fish enjoy living in a neutral pH range of between 6.5 and 7.5 and will adjust to anything in that range as long as the change is gradual.

On the other hand, abrupt changes in pH can end up stressing the fish enough for it to lose its color and fall ill.

Water acidity scales logarithmically, which means that 5 pH is 10 times more acidic than 6 pH and 100 times more acidic than 7 pH. A pH swing puts enormous stress on a Betta, and may even kill it.

This is why I would never recommend using acidity buffers in your aquarium (unless you know what you’re doing).

Also, Betta fish are often kept in smaller tanks, where pH swings occur more often because of the small volume of water.

5. Your Betta may be suffering from white skin lesions or fungus.

If the paleness appears local and the body or fin texture seems somewhat different at that spot, then your Betta fish may be losing color due to a skin disease.

  • Skin diseases such as Columnaris would form white or gray areas that do not reflect light the same way as the rest of the fish’s body. Columnaris rarely affects the fins.
  • The fish may also be suffering from fungi – white fuzzy formations that appear as a cottony growth on the Betta’s body.
  • Fins that appear to be unnaturally frayed with a fading color at the edges suggest that the Betta fish is suffering from fin rot.
a pale Betta fish swimming

By itsclassy

There are a plethora of fish diseases that could cause the formation of white spots on a fish’s body. You can learn more about treatments and see the visual symptoms of each disease in this guide.

What’s important to remember is that most of these conditions may be the result of environmental stress that has compromised the immune system of the Betta fish. Inconsistent water parameters and temperature fluctuations are often the underlying issue behind white patches or spots appearing on aquarium fish.

6. It may be exhausted from the constant presence of aggressive rivals.

Aggression and the lack of personal space among aquarium fish is a great contributor to a stressful environment. For example, Betta fish do not pass the mirror test and will aggressively flare at their reflection.

This can be mentally exhausting for a Betta, as it puts it in a constant state of fight or flight. Too much stress like this and your male Betta’s colors will inevitably start to fade.

The paleness caused by this type of stress affects all of the fish’s body, evenly.

You’ll likely need to make adjustments to the incoming light, in order to make sure that the tank’s glass is not creating unnecessary reflections.

Predominantly white Betta flares its gills

By aquabetta

Another thing to consider is having Betta live with compatible tank mates or in a moderately-stocked aquarium.

Fin nipping, chasing, and other aggressive behavior is a sure way to stress the fish, which can result in loss of color and pigmentation. Choose your Betta’s companions wisely in order to avoid any of that.

Having separate tanks with male Betta fish next to one another may still produce the same stressful environment as the fish will flare at each other.

7. Your Betta has the marble gene.

Marble Betta fish, as they’re called in the industry, have a type of “jumping” gene that can cause a natural change in their color.

As the gene jumps between different locations on a chromosome it may alter the skin pigmentation of Betta fish.

Furthermore, this process can happen several times during their lifetime.

If your Betta seemed to have splotches of color when you first got it, then there’s a high chance that it’s a Marble Betta possessing the jumping gene.

Sometimes these types of Betta fish can completely change or lose color and turn white. In this case, the color is not really fading, but rather disappearing altogether, giving way to a clear white or gray patch that grows with time.

It appears that the changes would more commonly start at the head of the fish.

Here’s a photo progression of a black Betta with the Marble gene, undergoing a dramatic color change:

before and after a black Marble Betta dramatically changes its whole body color to red

And here’s the very same Marble Betta turning its body color from red to pale pink and white:

Before and after progression of a Marble Betta turning from red to pale pink and white

By peachpeels

If the discoloration has not been sudden and is not accompanied by behavioral symptoms such as lack of appetite then your Betta may simply be changing its color pattern.

This process usually takes a week or more.

8. Aging

As betta fish age, they tend to naturally lose some of their color.

And since they have a short life span, the discoloration can occur as early as the second year of their life.

Unlike some of the other reasons, however, aging causes a more gradual shift in pigmentation.

What this essentially means is that the color loss isn’t nearly as dramatic as the one caused by stress for instance.

Older bettas simply have a slightly paler coloration, in contrast to stressed ones which can sometimes turn completely white.

While color loss in aging bettas typically isn’t a cause of concern, it can become one if it’s combined with lethargic behavior.

When both of these symptoms show up together, they usually indicate one of two things:

  1. The water parameters are off and the fish’s stressed.
  2. The fish has an illness or disease.

You can easily rule out the first by using a water test kit.

If there’s nothing wrong with the water then you should probably take your betta for a check up.

What to do to help your Betta fish return to normal?

There’s a series of steps that you can take to help your Betta regain its vibrant colors.

  1. Test the aquarium’s water. See if there’s anything off in the parameters.
  2. Perform frequent partial water changes.

    This is done to dilute the pollution in the aquarium and is an emergency response in case the Betta fish has been poisoned.

  3. Inspect the aquarium equipment and see if everything’s in order.

    Manually check if the filter and heater are running as they should.

  4. Feed the Betta fish with high-quality foods.

    Switching to a varied diet that mimics what Betta fish eat in the wild can have the largest impact on your pet fish’s recovery.

  5. Medicate the fish if needed. If the discoloration is caused by a skin disease, do some reading on the condition and medicate it accordingly. The most reliable way to identify what’s wrong with your fish is to take it to a veterinarian.

Follow these steps and your Betta fish will actually regain its usual color when the underlying issue is handled.

How to enhance the vibrant colors of a Betta fish even further?

If you feel like your Betta never has enough color and does not reach its full vibrancy potential, you could do the following:

The best way to enhance the pigmentation of a Betta fish is by feeding it food that’s high in insect protein and fiber. Providing a Betta fish with foods like midge larvae, water fleas, and shrimp could significantly improve the brightness of its body and fin colors.

How often and what volume of food you feed it are also things to keep in mind. In fact, I would actually recommend moving away from highly-compressed foods such as fish flakes and pellets altogether. Feeding on pellets or flakes exclusively can lead to severe belly bloat in Betta fish.

These foods contain land-based plants and gluten, but Betta fish are actually carnivorous and need to eat mostly insects, as they do in the wild.
Visit the link to learn easy ways to replicate a Betta’s natural diet at your home.

What eating a day of good food can do to enhance a Betta’s colors:

Colors of a Betta brighten after a day of eating bloodworms

By how_fedorable

Note that these types of foods will likely strengthen the overall health of your Betta fish as well.

A colorful Betta fish likely is a happy Betta fish

colorful Betta fish

By xShayla

There’s a good argument that a colorful Betta fish is a happy one.

Whenever it’s time to breed, male Betta fish should be in their top form to be selected by a female.

Studies suggest that body colors play part in the female’s choice, and so a male Betta should be as brightly-colored as possible. If yours is losing its color it could be a serious indication that something is wrong, unless you have a Marble Betta.

Simply, check if the fish displays other behavioral symptoms alongside the discoloration and act accordingly.

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Momchil Boyanov is the Founder and now Senior Editor of AquAnswers. He has over 13+ years of experience in keeping home aquariums as well as providing professional aquarium services. Momchil has had his fair share of adventures in aquarium care. He has made MANY mistakes throughout his fishkeeping journey and thus learned A LOT. Through Aquanswers, Momchil shares knowledge about freshwater and saltwater aquariums with the people within this community.

2 thoughts on “Why is my Betta Fish Progressively Losing its Color?”

  1. My beta Blu Boi is swimming sideways belly has large obvious largeness and im guilty of overfeeding. I have now since turned it around but he wont eat pea(ive tried 4 days in a row. Also, ive never ever seen bowel movement. Help.

    • Hi Janis,

      I have an article on bloated Betta fish – find it through the search bar and see if it helps.


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