Betta Fish Poop and Constipation – Causes And Treatment

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Betta owners love their fish – they’re feisty, beautiful, and make great pets in general. So, it can be especially alarming when our beloved bettas develop constipation. Your once healthy fish may begin to pass feces that look abnormal, and you might even observe behavioral changes. These developments can be incredibly alarming.

Thankfully, constipation is relatively easy to treat in most cases, as long as it is diagnosed early and treated rapidly. This article will explain exactly how you can go about doing so!

What Is Constipation?

Constipation happens when your betta has infrequent bowel movements, or poops irregularly. This happens when food has trouble passing through your fish’s digestive tract. When this happens, fish waste stops moving through its system in the usual way, effectively creating a blockage that becomes larger as your betta consumes more food.

It is important to treat constipation as quickly as possible to maximize your fish’s odds of recovery. When the condition is allowed to persist over extended periods of time, serious side effects may occur, many of which are dangerous and life-threatening to your fish.

What Are The Symptoms of Constipation?

Your odds of treating constipation in betta fish are greater the sooner you detect it. Here’s a list of signs and symptoms you should keep a lookout for.

Stringy Poop

The most common sign of constipation in betta fish is also one that’s incredibly easy to spot. Bettas with constipation tend to have stringy feces that dangle off your fish as it swims around. In contrast, normal betta poop sinks to the bottom of the tank once it has been passed.

Pale Feces

The color of betta fish poop can also give you some insight on the digestive health of your fish. Normal, healthy poop is dark brown in color, but bettas with constipation tend to excrete feces that are a lighter shade of brown. If your betta’s feces is both stringy and pale, this is usually a sign that it has constipation.

Note: Pale does not mean white! If your fish’s poop is stringy and white, this usually indicates that it has an internal parasitic infection rather than constipation. Constipated fish will also excrete stringy feces, but they are pale brown rather than white.

Bloated Stomach

Unfortunately, constipation is usually accompanied by a bloated stomach. The initial blockage prevents food from leaving your fish’s digestive tract, causing the blockage to expand in size as your betta consumes more food.

This ultimately results in a stomach that appears distended and bloated. Do note that constipation isn’t the only illness that is accompanied by a bloated belly. Dropsy can also cause similar symptoms, so be sure to assess your betta’s condition carefully to make an accurate diagnosis.

Lethargy and Lack of Appetite

The final symptoms we will cover are lethargy and lack of appetite. We’ve saved these symptoms for last because these generic signs are associated with a wide range of illnesses. However, they remain very relevant symptoms for fish with constipation.

Fish that are constipated will have a bloated sensation in their abdomen. The same way humans feel sluggish after a heavy meal, this bloated feeling can cause bettas to feel ill. This will cause them to swim a little slower, and steer clear of food for a while – at least until the sensation of fullness passes.

If you observe lethargy and lack of appetite in addition to the more specific symptoms mentioned above, it is likely that your betta has constipation. 

Why Is My Betta Constipated?

Female betta fish swimming

Now that we’ve learned to identify constipation, we should take a look at what causes it in the first place. This in turn will help you to avoid the risk factors leading to constipation. We always advocate for prevention as the best form of cure, so read this section closely and keep your fish’s digestive tract healthy!


Yes, you can kill your fish with kindness! Hobbyists can find it incredibly difficult to resist overfeeding their fish, especially when these fish enjoy food as much as bettas do.

However, it is important to not fall into this trap. Betta fish are notoriously greedy creatures who will keep eating long past the point of satiety, which can compel their owners to feed them more than they really need. Overfeeding your bettas makes them highly susceptible to constipation as it increases the risk of food blockages. This is definitely something you want to avoid.

Prevention: Feed Just The Right Amount

You can avoid overfeeding your bettas by feeding them an appropriate amount of food twice a day. How much is appropriate? Well, the general rule of thumb is to feed your bettas an eyeball-sized portion of food to correspond with the size of their stomachs.

Remember to soak your pellets and freeze-dried food first so you can get an accurate sense of how much you’re feeding your fish! These types of food tend to expand in your betta’s stomach, which can make it easy for you to overfeed by accident.

Poor Diet

Another leading factor for constipation is a poor diet. Unfortunately, many misconceptions exist about betta diets. People mistakenly assume that they are capable of surviving off plant roots, but this could not be further from the truth as these are carnivorous fish. 

In addition, many people make the mistake of feeding their bettas with low-quality flakes or freeze-dried food. This can deprive your fish of the essential nutrients it needs, making it more likely to fall ill.

Prevention: Opt For A Good-Quality Diet

A typical betta diet should consist of good-quality commercial flakes, supplemented by natural protein sources such as frozen brine shrimp, daphnia, and bloodworms. These protein sources replicate what your fish would eat in the wild, providing them with the nutrients and fiber they need to have a healthy digestive system.

Note: Always purchase your food from reliable sources, as live food sources may carry a risk of parasitic infections. We’ve all heard those horror stories of once-healthy fish dying from parasitic infections they got from a rogue bloodworm, so be very thoughtful about where you source your food!

Poor Water Conditions

Contrary to popular belief, bettas should not be kept in small bodies of water where the conditions may be less than ideal. Betta fish should be kept in at least 5 gallons of water with regular tank maintenance and tests to keep the aquarium water quality up to mark. 

In addition, betta fish will require an appropriate filter for their tank size, as well as a heater to keep water temperatures between 75-80 degrees Fahrenheit.

Prevention: Regular Water Maintenance

One of the best ways to keep your tank clean is by removing uneaten food. Uneaten food releases ammonia and nitrates as it decomposes, creating dangerous levels of both. In addition, they can clog up your filter, which can reduce the amount of dissolved oxygen in your tank.

Unhealthy levels of ammonia, nitrates, and poor oxygen concentration can all create parameters that are unhealthy for your betta, making them more susceptible to illnesses. Bettas should also not be kept in cold water, as this will compromise your immune system

In short, the key things you need to look out for are ammonia levels, nitrate levels, and temperature. We highly recommend investing in test kits which test for a myriad of water parameters – everything from nitrite levels to pH. A reliable thermometer is also a must-have, as you want to make sure that your betta’s home is properly heated.

Lack of Exercise

betta fish, siamese fighting fish in aquarium

Surprising as it may seem, bettas that lack exercise are also more susceptible to constipation. If you think about it, this makes sense. Food passes through your fish’s intestines via a series of contractions, and any form of physical movement can simulate these contractions.

Unfortunately, bettas tend to be rather sedentary fish by nature. They are likely to hover in place in various spots within the tank throughout the day – whether this is their betta hammock, or the tank floor.

Endearing as this trait may be, inactivity will not help your constipated fish in any way, shape, or form. 

Prevention: Get Your Fish To Move

Exercise plays a vital role in keeping health issues at bay. Encouraging bettas to exercise can be a little bit of a challenge as they are notorious for being sedentary. However, a good place to start is by introducing them to a larger home! Fish that are housed in larger tanks will be more inclined to explore their surroundings throughout the day, making this way to introduce movement.

Another way of getting your bettas to exercise is by relying on exercise mirrors. Some hobbyists are reluctant to turn to exercise mirrors as they believe that mirror reflections can be a source of stress. However, the general consensus is that using exercise mirrors for brief periods of time can be a good way for your bettas to relieve boredom by turning to their natural instincts!

In short, a stimulating environment will encourage your betta fish to move more. Be creative with toys, tank décor, and tank shape. Here’s a list of betta fish supplies to get things rolling. Your bettas will be up and moving in no time!

How Do You Cure Constipation In Betta Fish?

In spite of your best efforts, you might still find yourself with a constipated betta on your hands. Some fish are just more susceptible to the condition, and the best thing you can do is treat it early as soon as you notice something amiss.

Here are some things you can do if your betta is constipated:

Fast Your Fish

One of the best things you can do when you notice bloating or constipation in your fish is by fasting it for up to 24 hours. Feeding your fish while it is constipated will likely worsen the problem by creating a larger blockage in its intestines.

By fasting your fish, you give it the opportunity to pass hardened stool out of its system naturally, without relying on medication or other forms of intervention. Most mild cases of constipation will resolve themselves in this manner. 

Feed Your Betta Some Fiber

Woman feeding beta fish in aquarium at home.

The same way humans turn to prune juice when things are feeling a little congested, constipated betta fish will benefit from some added fiber in their systems. 

Fiber adds bulk to betta poop, which allows stool to pass more freely through your fish’s gut. In addition, fiber also absorbs and retains water, which makes your fish’s poop softer and easier to pass. 

Do note that bettas are carnivorous by nature, so these fibrous, plant-based food sources should not be made a diet staple as they won’t be fully digested. However, they can work wonders for a betta fish suffering from constipation. Here are some of our top recommendations!


Peas are a great source of plant-based protein and fiber, which makes it the perfect cure for constipation. Simply remove the outer skin of the pea, and cut it up into tiny pieces before serving it to your betta.

We recommend feeding no more than half a pea per betta, as overfeeding may backfire and cause the constipation to worsen.

Algae Flakes

For those of you looking for a source of fiber you can pick up at your fish store, this one’s for you. Algae flakes make an excellent source of dietary fiber for fish – after all, it’s what they eat in the wild!

If you happen to have algae flakes lying around the house for other fish, you can absolutely feed your constipated bettas with a small amount to alleviate their symptoms. However, we would recommend against purchasing algae flakes just for your constipated bettas, as these fish are carnivorous by nature!

Sweet Potatoes

Sweet potatoes are frequently used as a tasty snack for omnivorous or herbivorous fish, but they can also be a great way to fix your betta’s digestive woes. Simply cut a small slice of sweet potato into eyeball-sized pieces for your fish, and place it in the tank. 

We recommend against getting your bettas to bite pieces off a large slice of sweet potato floating on the surface of the tank, although this is common practice among owners of omnivorous fish. Doing so would introduce more air into your betta’s digestive system, worsening its symptoms of constipation.

Epsom Salt Bath

Magnesium sulfate (Epsom salts) in a rustic wooden scoop - relaxing bath concept

Ask any aquarist about Epsom salt, and you will likely get a laundry list of the many illnesses it can cure. In the case of constipation, Epsom salts work as a muscle relaxant, alleviating some of the tension in your fish’s digestive tract and allowing the food to pass.

To give your betta fish an Epsom salt bath, simply place it in a quarantine tank and add one tablespoon of salt per gallon of water. Let your fish swim about in the solution for between 15-30 minutes, or until it relieves itself. 

Note: Be sure to avoid performing this treatment in your display tank as Epsom salt can wreak havoc on your aquatic plants and tank décor.


What Happens If You Don’t Treat Constipation?

If you allow your fish to remain constipated over a prolonged period, your fish may develop severe constipation. This will significantly increase its risks of developing swim bladder disease, a bladder disorder that occurs when the abdominal cavity is compressed.

Swim bladder disease prevents your betta from swimming normally, which will make it difficult for them to feed or move about. In addition, bettas are labyrinth fish that breathe oxygen from the atmosphere. Swim bladder disease makes it very difficult for bettas to do so if they are trapped on the bottom of the tank.

What Is The Difference Between Dropsy and Constipation?

While a betta with dropsy will also have a swollen stomach, dropsy is caused by a buildup of fluid in your fish, while constipation is caused by food blockages.

In addition, dropsy can cause your bettas belly to take on a pinecone-like appearance, as the swelling may cause the scales to stick out and flare away from the body.

If you’ve confirmed that your fish has dropsy instead of constipation, here are some steps you can take to treat dropsy in betta fish.

Is It Good To Fast My Betta Fish?

Betta fish nibbling on gravel.

Many owners opt to fast their betta fish once a week or fortnightly to reduce their odds of constipation. In general, this is seen as an effective preventive method – especially if you have a fish that is prone to bloating.

The day of fasting allows your fish’s system to take a break and get rid of any blockages that have built up. This method is especially effective if you feed your fish with half a pea the day prior!

Can A Betta Die From Constipation?

The good news is, constipation alone will not kill your betta fish as it is not a fatal condition. However, the side effects of constipation that are left untreated can be dangerous and life-threatening.

Constipation that is left untreated will progress rapidly to become swim bladder disease. This is a stressful condition that prevents your fish from swimming normally. It is likely for feeding or breathing to become a problem if this is the case. This can significantly endanger your fish’s life.

In addition, constipation can make your fish more susceptible to more serious illnesses. Constipated bettas tend to be stressed out, which will in turn lower their immunity against other bacterial and parasitic infections. Many of these infections can be fatal.


Feeding Baby Bettas in the Aquarium with Frozen Baby Brine Shrimp

Whether you’re a beginner to the hobby or a seasoned aquarist, it is likely that you will encounter constipation in your pet fish. Bettas, much like most other types of fish, demonstrate symptoms such as stringy poop, lethargy, and bloating when they are constipated. We hope this article comes in handy if you ever find yourself in this situation!

Did you enjoy the article? If you found it helpful, do share it with someone in your circle who might find it more interesting. Until next time!

Wanda is a second-generation aquarist from the sunny tropics of Malaysia. She has been helping her father with his freshwater tanks since she was a toddler, and has fallen in love with the hobby ever since. A perpetual nomad, Wanda does her best to integrate fish-keeping with her lifestyle, and has taken care of fish in three different continents. She loves how it provides a nice break from the hustle and bustle of life.

1 thought on “Betta Fish Poop and Constipation – Causes And Treatment”

  1. Hi my gets constipated frequently. I fed him with peas it gets cured. After some days i started pellet food my poor betta again gets constipated.. pls tell me a solution


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