Do Tetras Sleep? (How And Why They Sleep?)

Image of a tetra swimming at the bottom of the tank

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Sleeping is an integral part of any living being, just like eating, breathing, and reproducing. Fish-keepers have experienced schooling fish like tetras in constant motion all day long. So, do tetras sleep?

Yes, tetras do sleep. Since tetras are diurnal fish, they sleep during the night when the lights are off. Tetras usually sleep near the gravel at the bottom of the tank. You can identify sleeping tetras by their unique characteristic of changing color when asleep. Tetras become pale while sleeping.

Like other animals, fish need regular sleep to stay healthy. Since tetras are very active, you may wonder when and how do they sleep. So, let’s take a deeper look into their sleeping patterns.

How Do Tetra Fish Sleep?

Tetras’ sleeping style is similar to other fish. Most of the tetras sleep at the bottom of the tank. Hence, they are called bottom dwellers. Some aquarists have noticed their tetras floating vertically near the gravel while sleeping.

Since most of the fish sleep with their eyes open, it becomes difficult to determine whether your fish is sleeping or not. However, with tetras, their color-changing ability while sleeping distinguishes them from other fish.

In broad daylight, you will find the lateral stripe on a tetra’s body to be blue-green; this color changes to indigo in darkness. When the tetras are awake, their color is vibrant, unlike pale when they are sleeping. This property of tetras to change color is associated with their sleeping.

Alright! Now that you know a tetra’s sleeping pattern, let’s also understand the signs displayed by tetras while sleeping.

How Can You Know Tetras Are Sleeping?

Most experienced aquarists are well aware of the signs that their fish display when asleep. However, if you are new to fish-keeping, it becomes difficult to determine whether your fish is sleeping or not.

When it comes to tetras, they are usually very active throughout the day. Hence, when they stay still in one place, you can say that they are resting. Since tetras are bottom dwellers, you will usually notice tetras sleeping at the bottom of the tank.

Following are some signs that tetras exhibit when they are asleep:

  • You will find tetras motionless at the bottom or near the surface of the water while sleeping.
  • If your tetras are floating at the same place without getting affected by the current, they are sleeping.
  • You will not see tetras reacting to things around them while sleeping.
  • While asleep, the tetras will breathe very slowly as compared to when they are awake. Hence, their gill movement will be slow.
  • Another way to determine if tetras are sleeping is by tracking their sleep schedule. Just like humans, tetras have a routine and tend to sleep at the same time each day.
  • The most effective way of determining whether tetras are sleeping is to notice their color change. Tetras while sleeping are pale in color, whereas they are vibrant when they are active.

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Why Do Tetra Fish Sleep?

Like any other tropical fish, tetras sleep to rest their bodies. Tetras are usually very active all day long. So, they need adequate sleep to rejuvenate their bodies. Besides, fish do not sleep as humans do.

Most fish species go in a restful state where they remain still for some time. While asleep, fish experience slow metabolic rates, reduced breathing, and lower brain activity. This promotes good disease resistance power and sound health. The same applies to tetras as well.

Also, adequate sleep ensures that the tetras are active and in good health. So, they sleep to conserve energy and restore their body.

Besides, lack of sleep is detrimental to the well-being of tetras. Sleep deprivation may result in lethargy and health-related issues in tetras. Also, it may even have an irreversible impact on their eating, digestion, and overall well-being. So, when you see tetras sleeping, it is better not to disturb them.

Do Tetras Need Light At Night While Sleeping?

Just like other fish species, tetras do not need light at night while sleeping. It is best if you switch off the aquarium light at night so that the tetras get adequate sleep.

Leaving the light on for a prolonged duration during the night may stress and frighten your tetras. Tetras need darkness for some time to rest. Besides, turning lights off at night mimics their natural environment.

Apart from the stress factor, excessive light results in algae bloom in the aquarium. Too many algae will make your tank look unhygienic. Besides, excessive lighting also increases the water temperature. This again is not conducive to your tetras’ healthy growth.

So, it is advisable to turn off the light at night so that the tetras can sleep peacefully.

Now that it is evident tetras need adequate sleep for sound health, let’s also look at the various ways to ensure tetras get enough sleep.

Related Further Reading:

How To Ensure Tetras Get Enough Sleep?

Just like all living creatures, tetras need quality sleep. This can be done by following their physiological cycle of staying awake during the day and sleeping during the night.

Given below are some ways to ensure tetras get enough sleep.

1. Use light timers.

The use of light timers is the easiest and widely used technique to ensure tetras get adequate sleep. With light timers, you don’t have to switch off the aquarium light manually. You can set up a time when the lights will switch-off every day.

Light timers will help to create a day-night routine for your tetras. The tetras will automatically sleep when the lights are off. So, it is the best way to keep things on schedule.

Another advantage of light timers is that they help to replicate the day-and-night cycle just like their natural environment.

2. Keep suitable tankmates.

Keeping suitable tankmates is another way to ensure that your tetras get adequate rest.

If you keep large and aggressive fish with tetras, they may not feel safe to sleep. This will result in stress and other health-related issues in your tetras.

Also, since tetras are schooling fish, suitable tankmates will make your tetras feel safe, and they will enjoy companionship too.

3. Provide sufficient hiding places.

Providing hiding places ensures that your tetras get a safe place to rest. Timid tetras can rest and sleep peacefully in hiding places without any fear.

Besides, providing a safe place to rest ensures that the sick and timid tetra do not get bullied. Decorations like caves, bridges, and tunnels offer a nice spot to rest in darkness.

4. Keep the tank in a suitable place.

Your tank should be placed in a room where there is silence. Tetras prefer a calm environment to sleep in.

If you have a TV with loud noise or people moving around continuously beside the tank, it will disturb the tetras’ sleep.

So, it is advisable to maintain silence at night to ensure that your tetras get adequate sleep.

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5. Manage other pets.

Fish get disturbed in the presence of other pets such as dogs and cats. So, if you have pets other than fish, you should ensure that they do not intervene in the sleep of your tetras.

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