Can Ember Tetra See In The Dark? Shocking Facts

Many people are curious about the ability of Ember Tetra to see in the dark. After all, they live in a black water environment with no light for most of their lives. However, there is little information out there on how these fish can navigate through the darkness or if they are even able to see anything at all.

No, ember tetra cannot see in the dark. Keeping an ember tetra in a dark room will cause it to die. It needs light to survive and can’t see anything in the dark without it. Yes, Ember Tetras do need light but there is no real answer on why they require this kind of environment. We know that having another type of lighting source would not be an option for Ember Tetras, but it’s still a bit of a mystery as to why they rely on light.

This article will answer some questions that many have about this fascinating species and provide answers as to why it is important for them to have access to an aquarium light!

So, Can Ember Tetra See In The Dark??

They cannot see in the dark. Since they live in the water, their vision is limited to what’s happening around them.

The Ember Tetra only needs a light for some days after you have transported them from its place of origin. Once that time period has passed, you can then switch off the aquarium lights and allow your tetras some dark time as well!

Ember tetras only need the lights on for around two days. After approximately two days, you can begin to lower how long your tetras are exposed to the lights.

Once they have begun living in their new environment, it is important that you feed them at least twice a day (morning and night) for around 30 minutes each time. This way, they will be able to maintain the necessary energy and nutrients that allow them to grow into healthy adults!

It is then recommended that you keep your aquarium light on for around 12 hours each day (either all at once or spread out throughout the day). If you choose to keep it on all at once, make sure not to leave it on for more than 12 hours, as this can disrupt their sleeping patterns.

How Do Ember Tetra Navigate In The Dark?

Ember Tetra navigates in the dark by using their lateral line, which is an organ that detects water pressure. The lateral line in ember tetras is highly developed and is used in a similar way to how bats use sonar.

When the tetras feel water pressure, it triggers their lateral line receptors, which then sends signals through the fish’s nervous system for directionality control.

What Happens When You Keep Ember Tetra In A Dark Room?

If you keep the tetras in a dark room, you can see them become disoriented and can become very sick. The aquarium needs to maintain its light schedule or it may affect their sleeping patterns as well! This means that if the lights are on for too long, then your fish might start thinking it is time to wake up!


Disoriented fish can sometimes swim in abnormal patterns which may lead to them becoming trapped under rocks or other surfaces. They will also stop eating because their hunger cues are thrown off, leading to malnutrition and eventually death if not corrected.

Becomes Sick

Ember tetras will become sick from the darkness because they rely on sight to navigate their surroundings. When you keep them in a dark room, it confuses and stresses out your fish.

Can Ember Tetra Live In The Dark Forever?

Ember tetras only need the lights on for a few days after you have transported them from their place of origin. Once that time period has passed, you can then switch off the aquarium light and allow your fish some dark time as well!

You cannot keep the ember tetra in the dark forever. You will require some light in the aquarium for them to see the surroundings. This will help reduce stress and anxiety in the fish.

Why Does Ember Tetra Need Light?

Light in an ember tetra tank is essential as it gives them a sense of direction when they are trying to navigate their surroundings. This also helps the fish recognize if it is night or day since ember tetras have a 24-hour schedule. The 24-hour schedule includes sleeping and eating during nighttime hours.

Helps In Digestion

Ember tetras need light because it helps them digest their food. The light stimulates a chemical reaction in the enzymes. This in turn allows them to better absorb nutrients from their food during digestion.


Ember tetras also utilize light in navigation in the aquarium. They cannot see in the dark. So, light helps them to know where they are going.

Safe From Predators

If there are many predators in the tank, there will be a lot of stress. When the ember tetras can see the predators, they can stay safe and reduce their stress accordingly.

How Long Should You Keep The Aquarium Light On?

I recommend that you keep your aquarium light on for around 12 hours. This will allow your tetras to sleep through the night!

Sinc remember tetras cannot see in the dark, I suggest you leave the light on. You can make a certain nighttime routine. This will help you ember tetras to get the required rest and sleep. The circadian rhythm will also be sound helping your tetras to be more healthy and happy.

Do Ember Tetra Like Colored Light?

Ember Tetras do not have a preference when it comes to colored light. You can switch between different colors or keep them on white lights, which is the standard for most aquariums. However, you should keep the light on for at least 12 hours a day, in order to give your tetras time to sleep.

I have listed some of the best tetra aquarium lights below for ease:


How Long Does Ember Tetra Sleep?

They sleep for around 12 hours every day. So, you can keep enough hiding spots in the aquarium and turn off the lights at night so that they can sleep soundly.

Can Ember Tetra See Outside Of Their Tank?

No, they cannot see outside of their tank. This is because the tetras are confined to an aquarium with glass walls and a lid on top! They also don’t have eyelids as humans do. This means that they can only stay awake for so long before their eyes start to hurt.


Ember tetras need 12 hours of light each day and you should keep them in a tank with white lights. This is the most common form that aquarium lights come in! They also require around 30 minutes worth of food two times per day (morning and night) for proper nutrition. But it will only eat if they are hungry!

Thus, ember tetra cannot see in the dark. You will have to put the lights on for a small amount of time. Additionally, you can close off the lights at night so that they can sleep well. If you understand the blog better, you will have a healthy and happy ember tetra in your aquarium!

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