Are Betta Fish Nocturnal? When do They Sleep?

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The sleeping habits of fishes are certainly not as obvious as ours. When do they sleep and how do they do it? In this article, I’m going to take the Betta fish as an example and talk a little bit about its sleeping habits.

Just like any other fish, Bettas do sleep and they do it while floating. They are just inactive during sleep, with only their gills moving. Bettas are not nocturnal so they follow a similar sleeping pattern like us, humans.

Therefore, they need darkness in order to sleep well. This doesn’t mean, however, that they don’t take a couple of naps throughout the day.

Next up, I’m going to answer the most common questions regarding the sleeping habits of Betta fish.

How Much do Betta Fish Sleep?

It is not as straightforward to tell exactly how much a Betta fish should sleep. The rule of thumb is to try to simulate the day and night cycle for them in the aquarium. This way, they are going to get sleepy when it gets dark and sleep as much as they need to.

How much they sleep is really not important. What is important is to provide the right circumstances for them so that they can sleep. This means that there shouldn’t be any lights on in the tank when it’s sleepy time for them.

In case they don’t get enough sleep throughout the night for some reason, they are going to take naps during the day anyway. The only mistake you can make is to leave the lights on during the night, which will cause your Betta fish to become sleep deprived on the long run.

Can Betta Fish Sleep with Lights On?

Bettas need darkness in order to be able to sleep. They can’t get enough sleep if you leave the lights on or TV is running in the background. Although they might be able to take short naps in the meanwhile, it certainly won’t count as a healthy sleeping pattern.

Bettas got used to sleeping during the night in their natural habitat. Setting up an aquarium for them as home is mainly about imitating their natural habitat. This also includes simulating daylight and the absence of light as well so that they know when to sleep.

They naturally fall asleep when it gets dark so in order to keep things natural for them, make sure to switch the lights off at the end of the day. You can help them maintain a natural sleeping cycle by ensuring 12-16 hours of darkness and 8-12 hours of light each day.

Can Betta Fish See in the Dark?

Bettas can certainly see in the dark but everything is blurry for them. This is mainly thanks to their iris which does not function the same way as ours. It is harder for them to adjust their eyesight when the light conditions change.

In the dark, the Betta fish relies on the lateral lines that you can see on their bodies. Those help them to orient themselves when the lights are switched off.

Do Betta Fish Play Dead?

Bettas don’t play dead but their respiration is reduced when they sleep, which is why might they seem like they are dead. Plus, they also tend to sleep on their side laying down and they are quite inactive in the meanwhile.

A huge indicator of your Betta having a health problem is when it swims upside down or sideways. It might seem like your betta plays dead but chances are he is actually sick.

Do Betta Fish Lay Down when They Sleep?

Usually, when fish keepers see their little pet laying down on its side, it means that the little guy is sick. Fortunately, this is not the case with Bettas. Sometimes they just lay down on their side and sleep that way. When they do this, they prefer sleeping on leaves.

If you see your Betta laying down when it sleeps, then just go to the aquarium and he will most likely wake up and swim. This way, you can confirm that there is nothing to worry about and he was just sleeping.

In case your Betta is laying on its side for a long period of time and seems lethargic, however, then it might be a sign of a health problem. One of the most common health problems that cause Bettas to lay down is swim bladder disease.

Wrapping Up

Betta fish do have a sleeping pattern just like we do and they are not nocturnal either. You can help your own Betta sleep well by switching the lights off at the right time. It is important to simulate their natural habitat so that they can live a healthy and happy life.

In case your fish is sleeping on its side for an unusually long time, then it might be a sign of an underlying healthy problem. Bettas are not hard to wake up so if you want to make sure your pet is alive and well, just try to wake him up.

He should start swimming right away just like he does throughout the day. If your pet is sick and you are not sure what to do, the best idea is to call the veterinarian immediately.

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
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