How Long Do Betta Fish Sleep?

Betta fish often confuse or frighten their owners. They behave unusually, without clear rules. They are stubborn, spoiled, or too aggressive. No matter how hard the owners try and do everything right – Betta fish often do everything the way they want. Although sleep is a natural and simple process – with Betta fish it is a little more specific.

Betta fish, like all living things, sleep. They need sleep to maintain their general health. However, owners’ experiences about the length of their Betta fish’s sleep are different. Some say that their fish do not sleep at all, others that they sleep constantly. Even experts are not sure how much sleep is best for a Betta fish, so they generally recommend that you follow their sleep rhythm or try to align it with yours.

Depending on the character, general health, but also the condition of the aquarium – Betta fish can sleep from 8-16 hours a day. While this may seem like too much of a range for one species of fish, the owner’s experiences say so. However, you should know that due to its nature – sleeping for a Betta fish is not the same experience as for humans.

Why Do Betta Fish Sleep So Short Or So Long?

Biologically, Betta fish are both prey and predator. This means that when they are in the wild – they are very easy to spot and quickly become food for larger fish. That’s why their sleep is more of a nap. They have no eyelids and cannot enter the REM phase of sleep, that is, deep sleep like humans.

Therefore, their whole body is always on guard, but they also need a lot of rest. Betta fish experts call it light sleep, precisely because they wake up very easily and quickly. 

When they are in the aquarium, they behave similarly, even though they have no natural enemies there. Sleep length or lethargic and passive behavior is what often confuses the owners of these fish. They are not sure if their Betta is asleep, sick or dead. 

There are no unambiguous indications that Betta the fish is asleep. The best way is to try to somehow train the Betta and go to bed at the same or approximate time every night. That way, you will be at least somewhat sure that the Betta has received its necessary dose of rest and sleep.

What Does Betta Fish Need For A Peaceful Sleep?


In the wild Betta fish sleep when it is night and since they are tropical fish they hide behind plants, empty shells or in the mud. In principle, they are not nocturnal fish, but have a biorhythm similar to terrestrial animals. 

However, since the tropic area is quite unstable, Betta fish have developed the ability to survive with lethargic behavior. When the water is dirty, there is no food or they are in danger, their color fades and they reduce their activity to passive floating or hiding. Such behavior is a kind of camouflage and has undoubtedly helped them survive to this day. Betta fish also need darkness in the aquarium.

Even during the day, it is not good for the aquarium to be in a sunny place, because the water could overheat. Place the aquarium in a shady place and be sure to provide your fish with at least 8 hours of complete darkness a day.


There are many types of plants you can put in your aquarium. It is important that they are not rough and do not occupy the entire water surface. Betta fish adore plants. They inspire them to be active, to explore, but also help them sleep and rest. 

Plants are especially important if you have a mix of fish species in the aquarium in addition to the Betta fish. That way, Betta will have a place to hide both when resting and sleeping, and it will be easier to neutralize natural aggression towards other species. Betta fish like to sleep on or behind the leaves.

Regularly Maintained Aquarium

A regularly maintained aquarium means that you try to make the Betta fish as natural and beautiful as possible. Betta fish are a bit demanding, but also very interesting fish. The aquarium must be larger; under no circumstances should you keep them in bowls or glasses. Such a small space is a trigger for stress and a kind of panic attack that can be fatal for a Betta fish. 

You need a heater, a thermometer and a water filter. If all of them work properly, your Betta will be happy and will be able to regulate the rhythm of sleeping, swimming and resting.

How Do I Know If a Betta Fish Is Sleeping or Sick?

The confusing behavior of Betta fish is also supported by the fact that they look almost the same when they are sleeping, when they are sick or dead. However, some shades may still differ.

Betta fish sleep in all poses: on their sides, heads bent, floating or to the bottom, hidden or on the very surface of the water.

If you are a careful observer, you will notice that while sleeping, the Betta’s gills are calmer and slower. The easiest way to know if Betta is sick or just napping is to splash water on the surface or touch the fish with a net. Since Betta has a light sleep – if everything is fine, he will react immediately. Don’t do this often because it causes stress, and Betta fish have a hard time coping with stress.

Betta Fish Sleep

If your betta fish is persistently lethargic and seems to be sleeping and resting more than necessary, check the water temperature first. They are very sensitive to temperature changes and if they do not return to the optimal level quickly they will get sick or die. Also, check the water quality regularly. 

Most Betta fish diseases are caused by poor conditions in the aquarium, i.e. due to great stress. If, on the other hand, you are convinced that you have done everything you need, that the condition in the aquarium is at an optimal level, and your Betta is sleeping for a long time – maybe it’s up to her character or simply your Betta is too old.


Betta fish sleep relatively long. Sometimes it’s a sign of illness, and sometimes it’s just character specificity. Excessive activity is not good either, because it is a sign of great stress or pain. 

So you have to observe your Betta fish and distinguish what is her usual behavior and what is not. This is the easiest and fastest way to notice irregularities and signs of illness.