Is My Betta Pregnant or Bloated?

Is your Betta pregnant or bloated? It could be either. It all depends on the symptoms.

When I was new to fish, I remember panicking after seeing them swimming around the aquarium with swollen abdomens, wondering what on Earth was wrong.

I soon learned that eggs take up a lot of space inside the fish and it’s perfectly normal for them to look a little swollen now and again.

However, I also know that there are times when bloating indicates a problem – something we will discuss below.

In this post, we will first discuss pregnancy and then bloating :

Is my Betta fish pregnant or just fat?

So, let’s get straight to the point. Generally speaking, if you notice your Βetta fish putting on weight, it is unlikely that it is becoming fat. Instead, the apparent weight gain is much more likely due to the buildup of eggs inside the abdomen.

Carrying eggs causes the fish to expand. If pregnancy is the cause of the weight gain, you will notice an enlarged vent – the part at the rear of the fish where the eggs come out.

There are some other reasons for a fat-looking Βetta. T

There is another condition called Malawi bloat that causes Betta fish’s abdomens to expand.
The classic sign here is trouble in breathing.

hese include dropsy – a disease that causes fish to become large – as well as certain tumors.

What does a Pregnant Betta fish look like?

Telling whether a Betta fish is pregnant is actually quite easy. You should notice some white vertical stripes on the female’s body. Males in the tank will produce bubble nests in anticipation of ovulation.

Furthermore, female Betta fish will have a round white patch on their stomachs if they are close to laying eggs. This region is called the ovipositor, an egg-laying organ that sits between the ventral fins. The belly will appear bloated in this area during pregnancy.

How long does it take for a Betta fish to give birth?

Usually, Betta eggs will hatch within around three days.

How did my Betta get pregnant?

Betta fish do not carry fertilized eggs inside their bodies. Instead, they produce and release eggs if they detect male fish in their environment. Males create bubble nests for the eggs and then fertilize them after the female ejects them from her body.

What Do Betta Eggs Look Like?

Betta eggs are small around 1mm in size and look like big white balls.

How can you tell a male Betta from a female Betta?

Male Betta fish will have a lot larger top, bottom and tail fins. A female will have less striking colors.

Is My Female Betta Fertile?

Female Betta fish that are fertile will present white vertical stripes on their bodies.
Female Bettas carrying eggs will have a round white patch on their stomachs.

Can Female Betta Fish Lay Eggs Without A Male?

Betta fish can lay eggs without a male being present.

Is your Betta Fish Bloated?

Now let us begin about bloating. The symptoms of Betta fish bloat depend on the underlying cause of the condition.

In some cases, the Betta fish may have swim bladder disease. Signs of this condition include trouble swimming and lack of appetite. In more advanced cases, you may also notice a curved back or the fish may appear overly lethargic.

Bloating can also be the result of poor water quality or poor diet. Τissue damage from dangerous objects in your tank can also cause it.

There is another condition called Malawi bloat that causes Betta fish’s abdomens to expand.
The classic sign here is trouble in breathing.

What Is Dropsy?

Dropsy is a condition of swollen bellies. It is caused by the accumulation of fluid inside the cavities and tissues of Betta fish. Typically, it indicates a number of underlying conditions, including liver dysfunction, parasitic infections and bacterial infections.

Symptoms Of Constipation in Betta

Finally, one of the most common causes of fish bloating is constipation

Lack of appetite is the most common constipation symptom that you will encounter. Most Betta fish will start eating immediately in the presence of food, particularly if you haven’t fed them for several hours. However, a constipated Betta will not want to eat.

Constipated Betta fish will also struggle to pass stool. So if you notice this in combination with lack of appetite, constipation is the most likely diagnosis.

Causes Of Constipation

There are two main causes of constipation in Betta fish: poor diet and lack of exercise. Betta fish should be eating high-quality fish food. They should also live in tanks larger than 5 gallons so that they can exercise.

How To Treat Constipation

Treating constipation in Betta fish requires fasting the fish for two or three days. After this time, you can then feed your Betta small fry, such as daphnia and mosquito larvae. If that fails, you can also try feeding peas that are high in fiber.


In summary, there are significant differences between a bloated Betta fish and a pregnant one.
It is unlikely that your Betta fish is getting fat. In most cases, a bloated non-ovulating Betta fish has constipation. You should be able to tell that the fish is ovulating by the white ovipositor patch between their dorsal fins. If that patch is absent but the fish still looks bloated, then your Betta fish may have a medical condition.

If you want to learn more about Betta’s behavior, advice, and tips, please visit our collection of Betta Tips Articles.

About the author

Hi, I am Alex.
My passion is aquariums. I am especially drawn to betta fish. I love experimenting, learning, researching, and writing about them.

You can find the articles I wrote here