Can Betta Fish See in the Dark?

Last updated on April 20th, 2022 at 05:21 am

All fish species have a bit of night vision, but bettas have slightly poor eyesight. Short distances, colors, and shapes are fine for bettas but they are a little near-sighted.

Vision is the most important sense for most animals, and betta fish definitely is not an exemption.

If you’re wondering whether your betta can see in the dark and do some form of activities, we’ll talk about them below!

Can betta fish see in the dark?

Bettas have a weak vision in the dark, but they don’t have clear eyesight, to begin with.

Their weak vision is because of the slow function of their iris, making it hard for them to adjust to different brightness and darkness changes.

But, bettas can still function well by using the lateral lines in their bodies. These are sensitive pressure sensors that are visible as a line from the side of the head to their tail and are in charge of detecting changes in water pressure and keeping the betta aware of its environment.

Every slight change to the pressure of the water in their tank is detectable, and when you drop food, they can detect it easily because of their later line.

This means that even with their poor vision, bettas can still “see” even in the dark.

Bettas need a healthy amount of darkness and while a betta kept in the dark is safe, they still need light to mimic their natural habitat.

Do betta need darkness to sleep?

Like some animals, betta fish have their day and night cycles. Betta fish need to sleep to restore their energy and health so both of you can enjoy each other’s company.

They are active during the daytime and sleep normally at night.

Some may nap from time to time while others like a long good night’s sleep. It may entirely depend on the personality of your betta fish.

If your betta doesn’t have enough darkness in its tank, you may see it trying to hide under the plants or toys to cover themselves.

To answer the question: Yes, your betta prefers darkness for them to sleep well.

If you find your betta at night swimming around actively, check if there are any light sources shining directly at your aquarium. Adding hiding spots for your betta fish is also ideal so they can have their own little sleeping areas whenever they want.

Their sleeping habits are pretty much the same as humans. If you don’t see your betta fish sleeping, it’s most likely that you are sleeping while they snooze at the same time.

Related: Can Fish Sleep with the Air Pump On?

What does my betta do at night?

What does my betta do at night

They swim around and play during the day, it’s also the ideal time to feed as they can find their way around their fish tank and easily find and eat their food.

Bettas are active during the day and sleep at night. You may find that your betta probably has the same sleeping patterns that you have.

If you’re curious about what they do at night, you can set up a camera and record their night activities. Alternatively, you can watch this video from another betta owner.

Do bettas like light?

Keeping your betta fish in the most natural environment keeps them happy. Try to replicate the conditions of the common betta fish habitat.

In the wild, betta fish live in rice paddies, marshes, and river basins. Being in the wild means they experience light from natural sun rays and darkness at night with some light source from the moon.

Most of their environment has dense aquatic vegetation where water is muddy and is naturally dark. Wild bettas can thrive in murky waters, but clean and clear water is much preferable.

In the wild, bettas can easily spot their food in the daytime when it’s bright and eat on the surface of the water.

A pet betta fish has a different environment. An artificial light source, water heater, some plants, substrates, and some toys are what they live in.

Betta fish like light, in the sense that they like and need it to stay active, find food and see clearly.

If you’re new to fish keeping or want to be a betta owner, then having a light source for your betta is one of the first steps you should do. That’s the topic we’ll talk about below.

Related: Do Bettas Like Light? All Your Questions Answered!

How to keep an aquarium light in your betta tank?

Artificial and natural light are easily available and betta fish need to have a stable source for up to 12 hours per day.

It’s important to know that having too much light can lead to overstimulation, making it hard for your betta to rest and restore its health to function well.

This may also confuse your betta as it won’t know the feeding time anymore, which will then lead to stress.

Make sure not to leave your betta tank light on or off for too long.

If you’re looking for which light is best for your betta fish, these are the three common light sources you may consider:

Natural sunlight

The natural sunlight encourages live plants to grow, but the disadvantage is the algae growth that may result in bacterial infections.

Remember to avoid direct sunlight though as this could do more harm than good to your betta.


LED lights have color tones that produce soft, cool, or warm lights for your betta fish tank. Opt for 1 watt per gallon if you plan to buy an LED.


Fluorescent light produces a steady light source and is warmer than LED. They are typically what you use at home, so you can find this type on any local hardware. Install around 1.5-3 watts of fluorescent light per fish tank gallon.

These light sources produce heat, so make sure to check your fish tank’s temperature as warm water can lead to irreparable damage and long-term health problems to your betta.


Fish are sensitive individuals and function on their senses, not just their eyesight. Betta fish can see in the dark, but they mostly use their other senses and rely on their lateral line.

They don’t particularly dislike the dark, but they prefer the daytime because it’s when they can actively swim around and find food easily.

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