Can Betta Fish See Their Food In The Dark?

Can Betta Fish See Their Food In The Dark

It is recommended to feed Betta two times a day: morning and evening. Many beginner betta keepers often wonder if their betta will be able to see the food after they turn off the light at evening? Can betta see foods in the dark?

Betta fish can’t see their food in absolute darkness. Betta’s eyesight is not very strong, particularly in the dark. So, if there is absolutely no light, the betta won’t be able to see the food.

Betta’s eyesight is very interesting. Betta’s and human’s eyesight has much similarities as well as dissimilarities. In the rest of the article, I’ll explain more why betta can’t see well in the dark as well as how their eyes works.

I promise you, knowing these will make you a better betta keeper!

Why Betta Can’t See Their Food In The Dark?

First of all, Bettas don’t have as strong eyes as we do. Comparatively betta’s eyesight is much better than other fishes, but that doesn’t compare to ours. This is primarily because bettas have very small Iris.

For those who don’t know what Iris is, it is the opening in our eyes that let light enter through our eyes and hit the retina. Practically Iris is the gate that determines how much light will enter inside our eyes. If the Iris is larger, then more light will enter and vice versa.

Iris has another amazing functionality. It can react to the intensity of light and change its size. Suppose, if there is high light around us, the iris will shrink so that it can limit the amount of light that enters our eyes. This is also called Iris dilation.

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On the other hand, in a low-light situation, our eyes will need more light to see. As a result, the iris opens up, allowing more light to enter and hit the retina.

This sensitivity of Iris is very quick and adept in Humans. Whenever we turn on the light in a completely dark room, for a few seconds, we can’t see anything clearly. After about a minute, our eyes get adapted to the high light and we can see everything clearly. Same goes when we enter in a completely dark room suddenly from a high-light environment. Our Iris help to adjust our eyes in the new environment.

As bettas have very small Iris to begin with, they allow a very limited amount of light to enter through the eyes. This is okay in a high-light situation. However, the betta won’t be able to see anything when there is no light.

That’s why, in the dark, Betta fails to detect the presence of very small food particles.

How Betta’s Eye Works?

I have already mentioned that Bettas and we humans have much similarity in terms of our eyes. There are some dissimilarities too. In this section, I’ll quickly go over how betta’s eyes works.

Trust me, the information is very interesting and it will help you to know your betta better!

Slow Iris

I have already told that Betta’s have small Iris compared to us. Their Iris has another weakness. That is, the sensitivity of the Iris is not as fast as us.

Our eyes can quickly adapt when there is change of intensity of light in the environment. For bettas, it can take from half an hour to even an hour.

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That’s why, you shouldn’t turn ON the light of the Betta tank suddenly in a completely dark room. It will cause harm to the betta’s eyesight and make it stressed.

If you want to turn ON the light of the betta tank, make sure you turned ON the light of your room at least half an hour before. It will give the betta enough time to adapt with the new light situation.

Monocular Vision

Another dissimilarity between Betta’s and human’s eyesight is the type of vision we see. Humans have Binocular vision. It means, both of our eyes see the same image. It helps us to focus on a single object. This type of vision is more common in predator animals.

On the other hand, Bettas have monocular vision. It means, each of their eyes see a different image. This interesting capability helps the bettas to stay alert for any potential danger and predator in the wild.

Why Betta Doesn’t Run Into Other Decorations In The Dark?

Till now, I have talked about 2 major disadvantages of Betta’s eyesight: slow iris movement and small iris. These 2 disadvantages are responsible for Betta’s comparatively weaker eyesight than us.

However, bettas have another amazing power that we humans don’t. This amazing power helps betta to have a sense of the surrounding environment even if there is no light. This power is more like the sixth sense of betta. Enough introduction, I am talking about the lateral line of betta.

This lateral line runs along the side of the betta’s body. It is present in most of the fish. This lateral line consists of pressure sensitive receptors. These receptors can sense change in the pressure of the surrounding water.

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As a result, the betta can understand something is around it. The receptors help the betta to understand if there is any obstacle ahead. Also, these receptors keep the betta safe during night by alerting it of any nearby predators.

Thanks to the lateral line, Bettas can comfortably move around in the tank at night.

Can Betta Fish Eat In The Dark?

The question is pretty much self-explanatory. As bettas can’t see food in complete darkness, there is no chance of eating the food, right?

However, if there is some ambient light around the tank, then the betta might be able to see the food, or at least sense the food. In that case, the betta will surely try to eat the food.

Can Betta Fish Sleep In The Dark?

Betta fish can sleep in the dark. In fact, bettas can’t sleep when there is light. That’s why betta experts always recommend to maintain a day-night cycle in the betta tank. Both day and night is imperative for a betta’s healthy growth.

If there is no light, the betta will always remain inactive. It will interfere with the betta’s regular bodily functions and growth.

On the other hand, if you keep the light turned ON 24 hours, then the betta will not be able to sleep or rest. That’s why, we need to maintain a rhythm. This is called the Circadian Rhythm.

Ideally, the betta should have 12 hour long day and 12 hour long night. But if that’s not possible, try to keep at least 8 hours of light.

Muntaseer Rahman

About Author

Hello, I’m Muntaseer Rahman, the owner of I’m passionate about aquarium pets like shrimps, snails, crabs, and crayfish. I’ve created this website to share my expertise and help you provide better care for these amazing pets.


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