Do Fish Sleep?

Like all living things, fish sleep. In the life cycle, all living things spend certain times of the day with less activity or sleep. Although it is difficult to understand that the fish is sleeping because it has no eyelids. Rest and sleep are essential to keeping the metabolism healthy. This rest and sleep process varies according to the species. The aim is to minimize the functioning of organs, slow down vital functions and collect the energy needed by the body as much as possible. Fish like us get sad if they don’t get enough rest and swim more slowly. It is essential for fish to rest for their health.

Some fish are more active at night and rest during the day, while some species rest at night. Some species are not bothered by light, others prefer the dark night to sleep. According to the species, the sleeping times of the fish may differ and there may be exceptions. However, in general, many fish species prefer to hunt for food during the day and sleep at night.

How Can I Tell If My Fish Is Sleeping?

If your fish looks at one point without moving, this is one of the symptoms of sleep.

If you watch the movements of the fish for a while, you can make the distinction between the times they sleep. If your fish is at the bottom of the aquarium, parallel to the bottom, or swimming very slowly, it is probably sleeping. If the fish does not react when you feed while in this state or its reaction is rather slow, it means that it is only waking up from sleep.

While the fish are sleeping, they only work their gills. Because they must maintain the oxygen level in their body. Some of the dormant fish do not swim at all, some only move their fins, some only their tails. In short, sleep patterns vary considerably according to fish species.

Sleeping fish can hang in the water without moving their tail and fins, although the fish do not move when they sleep, they do not fall to the bottom of the water. They do not even rise to the surface of the water. This is because they have a highly developed swimming bladder. Thanks to this stabilizer pouch, they easily balance in the water while sleeping.

Fish also use this pouch to go deeper. If they want to go deep, they can do so by ejecting air in droplets. The fish’s need to rise to the surface of the water is due to this sac. One of the reasons for fish to rise above water is to fill the air sacs. In this way, fish can stay still while sleeping.

What is interesting is the way fish’s brains work. In fact, we can say that this is the main mechanism that allows them to sleep by being suspended in water. While one side of the brain is sleeping, the other side is capable of breathing and swimming. In this way, the fish can sleep while swimming.

Do Betta Fish Sleep?

Betta fish, like all living things, sleep. However, betta fish sleep is very light. That’s why betta fish wake up at the slightest movement, light, and sound. In fact, betta fish, which are very safe in your aquarium, sleep lightly due to their nature. Bettas are active during the day and generally prefer to sleep at night. Turning off the light at night and being in a low-light environment makes it easier for the betta fish to sleep. People who meet the betta fish for the first time with the aquarium hobby may think that they are dead when they first see the betta fish sleeping at the bottom of the tank. Whereas the betta fish is making a little nap 🙂

Why Do Fish Not Have Eyelids?

The function of the eyelid is to protect the eye from wind, dust, and similar external factors and to keep the eye moist. In general, fish do not need an eyelid, which functions the same in all living things. Because they don’t need to keep their eyes moist while they are already in the water.

Do Fish Need Anything to Sleep?

Of course, there is no material for a fish that could be a special sleeping place sold as a nest. But ultimately the fish also choose a place to sleep. Some species of fish prefer to sleep in hollows, some among rocks, some by being buried in the sand at the bottom, and some by hiding among the leaves of plants.

Sleeping areas and sleeping hours of fish species differ. For example, beta fish sleep when the lights are off, while stingrays sleep during the day. While parrotfish sleep in the sand at night, goldfish love to sleep in the dark at night and prefer secluded corners.

You should consider this when decorating the aquarium according to your fish species. For example, Beta fish like to sleep among leaves. For this reason, a plant with plenty of leaves and especially large leaves that can be easily hidden should be placed in the beta tank. If you own a goldfish aquarium, it’s a good idea to have broad-leaved plants for your fish and decor with no sharp edges that can provide a nooky corner.

By creating areas suitable for the type and taste of your fish, you should create sleeping areas where you can rest well.

Should I Turn My Fish Tank Light Off at Night?

Imitating the natural life of the fish in the aquarium inside the house makes the fish healthier. Therefore, you should remember that your fish also need darkness.

Light is necessary for your fish to be healthy, bright, and vibrant in color, and even appetite and healthy digestion. However, fish also have night and day perception in their natural life. 12 hours of light a day is sufficient for fish. In natural habitats, fish wake up when the day comes to light and feed and swim in flocks, and at sunset most of them rest.

You should also provide a similar cycle in your home aquarium. Many fish lovers avoid turning off aquarium lighting for visual display. However, this may cause the fish to disturb the day and night. For this reason, do not forget to turn off the aquarium light at night.

🐠𝙃𝙋 Team
🐠𝙃𝙋 Team
We're just like you - aquarium enthusiasts who love aquatic life! We've been caring for and breeding all sorts of freshwater and marine aquarium fishes, plants, and other pretty little creatures for years. We love sharing our knowledge with other fish hobbyists, and this article you have just finished reading is the best proof of that. You can read more about us here.

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