Betta Stress Stripes: Detecting Health Problems Line By Line

betta stress stripes
Japanese Fighting Fish is reader-supported. When you purchase through one of our links we may earn an affiliate commission (at no extra cost to you).

Last Updated: September 4, 2023 by Flora Gibbins

Hiding, jumping, swimming at the top of the tank—Betta fish react to stress in different ways, a lot of which fish keepers will find difficult to overlook. However, it’s also true that Betta splendens show signs of stress that aren’t as overt, one such sign being stress stripes.


You might not notice your Betta’s stress stripes due to how well they blend in on these colorful fish. However, if you pay close attention, you can identify stress stripes among your pet’s scaling. This article reveals the underlying causes of and how to treat Betta stress stripes.

About Betta Stress Stripes

stressed betta image

One of the many ways stressed Betta fish react to sudden changes in their environment is by developing stress stripes across their bodies. Typically, a Betta reacting to stress in this way may lose its bright colors, with light and dark stripes becoming more prominent on its body.

Betta stress stripes look like horizontal lines on a Betta fish’s body. There’s no rule as to how wide they appear. However, if the stripes accompany a loss of luminance in your Betta’s complexion, your fish is stressed. You’re more likely to see stress stripes on female Bettas than on males.

Unlike female Betta fish, male Bettas get lighter in color instead of developing stripes. Also, males tend to display other signs of stress.

It’s important not to mistake stress stripes for breeding stripes; while stress stripes typically run horizontally, breeding stripes run vertically across Bettas’ bodies. Meanwhile, fear stripes are a step up from stress stripes and signify a Betta under extreme stress.

Making a note of what direction the stripes run (vertical stripes for breeding, horizontal stripes for stress) is the easiest way to tell the difference between them.

Common Symptoms That Accompany Stress Stripes

Your Betta may display the following symptoms when its color dulls (males) and stress stripes appear (females):


betta fish hiding in a fish tank with plants and pebbles

Hiding is a normal Betta fish behavior. However, if your Betta is doing it too much, it could signify that it’s under significant stress. Unfortunately, the hiding may make it challenging to see the stress stripes.

Diminished Appetite

floating food in a fish tank with betta image

Once you see a lot of uneaten food floating on the water’s surface, it’s a warning sign that your Betta fish isn’t eating. While it’s true that Bettas may reject food simply because they don’t like it, it’s also true that the underlying cause of the behavior may point to a more sinister disease symptom.


betta fish swimming in aquarium tank

If you notice your Betta fish flitting around erratically, it could be that it feels threatened. Note that this symptom is common only in a community tank setting.

Causes of Betta Fish Stress Stripes

Your Betta may develop stress stripes for a variety of reasons, some of which include:

New Environment

The most typical factor behind the development of Betta stress lines is a change in the fish’s environment. For example, when your new pet arrives from the pet store and you transfer it to its new tank, you’ll notice stress stripes on its body.

Fixing the Issue

There isn’t much you can do to fix things besides exercise patience. As long as the tank conditions are optimal, the stress stripes should disappear after a couple of weeks, during which time the fish would’ve acclimatized to its new surroundings.

Altered Surroundings

Similarly, you might stress your fish if you change its environment. For example, altering the position of ornaments and other environmental props in the Betta’s tank while cleaning may raise the poor fish’s stress level—even when you made the changes for its benefit. From the Betta’s point of view, an established territory has been lost.

Fixing the Issue

Again, you’ll have to play a waiting game when an altered environment is to blame for the Betta stress stripes. While waiting, believe in your Betta’s will to dominate. Once it has reacquainted itself with its surroundings and established new territories, the stress stripes should disappear.

Poor Water Quality

When the water parameters in the Betta tank go out of whack, or there’s a significant dip in water quality, your pet fish may develop stress stripes.

Fixing the Issue

In this scenario, you need to ask yourself a couple of questions: How regularly and consistently do you perform water changes? Are they too drastic?

It’s important to check the water quality regularly as water may lose its cleanliness due to a build-up of ammonia, nitrites, and nitrates resulting from decaying food and Betta excrement. And it’s a good idea to make gradual adjustments to the water parameters when making water changes.

The stress stripes should disappear when the water parameters become acceptable to your Betta.

Undesirable Tank Parameters

Your pet’s stress stripes may have little to do with the water quality or any changes you made to the position of tank props. Instead, it may be unhappy with the tank filter’s current or the brightness of the aquarium lights.

Fixing the Issue

You could lower the filter’s current if it proves too strong for your Betta. After all, these tropical fish don’t like strong currents. Additionally, lowering the brightness of the aquarium lights may help curb algae growth and reduce your Betta’s stress.They aren’t used to bright light in the wild.

Feeling Confined

Forget what you’ve heard; a small tank isn’t enough to make your Betta happy. Not only will your Betta stress out from the lack of space, but the lack of hiding spots will get to it too, resulting in odd fish behavior like jumping (if the tank has an open lid) or other stress signals commonly displayed by stressed Bettas.

Fixing the Issue

Consider investing in a bigger tank. For a minimum tank size, Bettas should be kept in 5-gallon tanks. Including live plants (or silk plants) kills two birds with one stone by mimicking your pet’s natural environment while providing places for these solitary fish to retreat to.

Other Tank Mates

Bettas don’t play well with company, being a highly territorial and aggressive fish species.However, it’s still possible to keep them in the same tank with other fish. For example, female Betta fish aren’t as aggressive as male Bettas, so she should be fine if her tank mates aren’t fin-nippers, right?

On the contrary, you might still notice stress stripes on a female Betta’s body, even though she hasn’t gotten into a skirmish with her tank companions.

Fixing the Issue

Bettas prefer their own company, so sharing the same space with more active fish might stress them out. Consider separating your Betta from the other tropical fish if you notice stress stripes.

And yes, you should do this even if you don’t see any injuries or your male Betta isn’t showing aggression to his roomies.


Despite your earnest fish-keeping efforts (cleaning the tank regularly, providing it with enough food, and the like), it’s still possible for your Betta to experience ill health.

Fixing the Issue

You can test the water to determine whether it’s causing the issue. Use a thermometer to check whether the temperature has dropped below optimal levels, as colder water can hinder a Betta’s normal digestive function. Bettas like warm water with 75 and 80 degrees Fahrenheit temperatures.

Also, besides water temperature, checking for changes in water hardness may help you get to the bottom of the problem, as Bettas find it difficult to tolerate hardness higher than 20 dGH.

Additional Ways to Relieve a Betta’s Stress

In addition to the above solutions, there are other things you can do to relieve your Betta’s stress. They include:

Feed It Good Food

betta fish eating food in an aquarium

Betta fish require a high-quality protein-based diet. They’re carnivorous, so meat should feature heavily in any food you feed them, whether pellets, frozen food, freeze-dried food, flakes, or live food. Avoid food products with fillers and more vegetables than meat; otherwise, your fish won’t be as healthy in the long run, leading to stress and, eventually, stress stripes.

Treat Illnesses

Bettas are susceptible to illnesses like swim bladder disease, which may persist even after you’ve made the necessary improvements to the Betta’s environment. Treating such conditions will require over-the-counter medications explicitly formulated to treat them, so make sure to diagnose your Betta’s stress stripes thoroughly.

Banish Boredom

If you haven’t already, provide your Betta fish with some aquarium props to stave off feelings of boredom. However, ensure that anything you include in the tank doesn’t have sharp edges that can snag your Betta’s flowing fins.

Additionally, making your Betta flare at its reflection should help awaken its territorial instincts, fighting stress-inducing boredom. 

Use Tannins

Consider adding tannins like almond leaves to the tank water. They’re an excellent way to regulate the water’s pH levels, which goes a long way to keeping Betta stress stripes in check.


Can Bettas die if their stress isn’t relieved?

Yes. Prolonged stress will leave your Betta vulnerable to infections and diseases, which may prove fatal if left untreated. Moreover, stressed Bettas may lose their appetite, which will crater your Betta’s health.

How long does Betta fish stress last?

It depends on what’s causing the fish to stress. For example, if you introduce a Betta fish to a new aquarium, it may take about a month plus for the fish to acclimatize to the unfamiliar surroundings. During that time, the fish will remain stressed. Conversely, stress symptoms caused by an issue with the tank won’t be relieved until you intervene.

Aren’t there striped Betta fish?

No. While Betta fish come in an assortment of colors, sizes, body types, and patterns, there isn’t a variety of Betta with a pattern that looks like stripes. However, Betta breeders continue to create new variations of these fish through selective breeding, so maybe a striped variety will emerge in the future.

Can male Bettas get breeding stripes?

No, breeding stripes are only typical to female Bettas. Male Betta fish don’t display any physical changes during breeding. So the only way to tell that a male is ready for breeding is when it makes a bubble nest.


Like most living things, Betta fish get stressed. One of the many ways you’ll notice they’re experiencing stress is through stress stripes, which develop horizontally on their bodies.

Many factors cause Betta fish to develop stress stripes, a few of which include bad water quality, an altered environment, and the presence of other tank mates. However, if you make the necessary adjustments, you can help relieve Betta’s stress.

It’s important to keep in mind that stress stripes may be caused simply by introducing the Betta to a new environment, in which case your best bet is to wait until your pet acclimatizes. Then, the stress stripes should vanish without any intervention on your part.

About The Author

Leave a Comment

Your email address will not be published. Required fields are marked *