How to Tell the Gender of a Betta Fish

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The betta fish is one of the most popular types of fish that people choose to keep as a pet, and there are many reasons for this. These fishes are extremely beautiful, they are graceful, and there are also more than 70 different types of this fish, so you don’t have to just go with something that everyone else has.

They are really interesting to have, and you can spend hours looking at them and studying their behavior. In this article, we are going to tell you more about bettas, and what you need to know about them before purchasing one. Continue reading if you want to learn how to tell the gender of a betta fish, and how to easily spot the dissimilarity between the males and the females even if you’ve never seen them live before.

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Vibrant colors

There are many things that differentiate the males from the females, and the first one is the color of the fish. When it comes to males, they have much brighter and strong hues. They are usually colorful, even though you can also find fishes that are in just one color. Note that experts suggest that females usually have more dull hues, and they are not as bright as the opposite gender.

One thing that you should know when it comes to shades is that females can also have vibrant hues, so make sure you pay close attention to other determining factors as well and don’t rely solely on this.

Fins and body form

The next thing you should pay close attention to is the fins. When it comes to males, they usually have much longer fins, and the horizontal ones may be shorter than the vertical ones. You should also look at the thickness of them, as the females will have a lot thinner fins when compared to those that the males have.

When it comes to body figures, the males are thinner, and they have long and slim bodies. When it comes to the opposite gender, the females have shorter bodies, and they may be a bit wider when compared to the males.

On this website, you can see that you can notice some of the dissimilarities even when you don’t see the fish in front of you, and even from the size and the structure of the bettas, you can easily notice what their gender is. The best thing about these fish is that they are easily recognizable, so you don’t have to be an expert to determine if you are looking at a male or a female.

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Note that when females are ready for mating, they will display vertical stripes on their bodies. Males will never have any types of stripes on them, so you should look at this part as well. However, if you are purchasing a young fish that is still not ready for mating, or if you don’t purchase them at the right time, you may not be able to notice this dissimilarity, because, as we mentioned, females only display these stripes when they are ready to mate with their partners.


Now let’s talk about the membrane that the bettas have, which is also known as their beard. This membrane can only be seen when the fishes flare their gill plates and you can notice a big contrast between the membrane of the females and the males. Males exhibit a much larger membrane, and sometimes it can be also noticed even when they don’t flare their fins, so you should look for it when trying to determine the gender. On the same note, females don’t have that big of a membrane, and they need to be flaring if you want to notice their beard.

Another thing that you should know about flaring is that the females tend to move down when they flare, and they are more likely to keep their heads down during this process. On the other hand, when it comes to males, they will never move their heads down, and they are more likely to remain horizontal throughout the process.

Personality traits

If you have more time to study the bettas, you can also notice some deviation in their overall behavior. The males are much more aggressive and they are also territorial. They will never be allowed to be in the same tank, and they are more likely to attack one another until there is only one of them left.

Because of this, experts suggest that you should never keep more than one male in your tank, and you should pay attention to their overall behavior. On the same note, females are not territorial as well, and they are much more friendly and calm. You can have as many females as your space allows, and they will not attack each other.

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Ovipositor tube

The last thing we are going to talk about is the ovipositor tube or the egg spot. The females of the betta fish have this tube or spot right under the head, near the bottom fin. Sometimes males can develop this part as well, and it causes confusion, but you should know that this is a rare occurrence, so if you can notice the ovipositor tube, chances are, the fish you are looking at is a female.

One thing you should know is that this tube usually develops later, so if you are looking at a young fish, you may not be able to notice it. However, if the betta is mature, then you should have no problem spotting it. The easiest way to see it is to give it some food, so that it swims vertically, exposing the neck.

These are some of the ways you can determine the gender of the betta. Compare them to each other, and try to spot the variation between each other. Some users suggest that you can even place a mirror inside the tank, and see if some of the bettas try to attack the mirror. As we mentioned before, the males can be extremely aggressive, so chances are, the males are going to try and attack the mirror. However, you should never do this for more than just a few minutes, and you should never leave a mirror in the tank permanently. If you have any trouble determining the gender of your fish, you should just talk to a professional and ask for their help.