How to sleep fish


How to sleep fish in an aquarium

If we have an aquarium, then most often we watch the fish when we are awake: in the morning, in the afternoon and in the evening. And we don’t always think about what our pets are doing at night. But after all, all living creatures need rest and sleep, which means that it is also necessary for fish. But how do you know that a fish is sleeping, because its eyes are constantly open? Let's try to understand this question.

What is a "fish" dream

Generally, speaking of sleep, one usually means the natural physiological state of the organism, when its response to the surrounding world is reduced, and the level of brain activity is minimal.

This happens in humans, mammals, birds, some insects and fish. On average, people spend a third of their lives in a dream (with a duration of sleep eight hours a day). In these time intervals, a decrease in heart rate and respiration occurs, the muscles relax. Such a state can be considered a period of inactivity.

But the fish are very different from the rest in biological functions of the body. Consequently, the dream they have is not quite familiar to us way.

  • The environment in which they live, as well as the features of the external and internal structures do not allow them to completely disconnect from the surrounding reality.
  • They do not have an absolute unconscious state, and they do not cease to fully understand the world around them.
  • Their brain activity remains almost unchanged.
This means that they do not fall into a deep sleep.

The sleep time of these underwater inhabitants depends on the type of fish. Those that are active during the day rest at night and vice versa. For example, a catfish hides all the bright time in a secluded place, practically does not move, and only at nightfall does it begin to swim and look for food.

What do the fish look like in a dream

Getting into the embrace of morpheus, the fish do not close their eyes. After all, they have no eyelids, and water constantly cleans their eye surface. However, the absence of eyelids does not interfere at all, since at night it is quite dark, and those fish that sleep during the day, specially swim to cover or shade the plants.

Fish that sleep can simply lie on the water, during which their gills will wash. Some can cling to the branches and leaves of plants. Other belly or side lay down on the bottom. Still others hang in the water column. In an aquarium, the sleeping fish most often drift at the bottom of the aquarium, making almost no movements, sometimes they can barely see the swaying tail. But with any, even the smallest effects of external factors (be it a danger or potential prey), they instantly revive and return to their normal state.

Briefly hibernation in winter and summer

Some species of fish at the onset of the cold season fall into the so-called hibernation. These periods, of course, differ from what we are accustomed to understand under the dream. But, nevertheless, it is also a sleep cycle.

During it, the metabolic processes in the body also decrease, all physical functions slow down, and the fish is inactive. At this time, she either hides in the shelter, or remains at the bottom of the reservoir.

And there are those fish who prefer to sleep during periods of heat. So they are protected from dehydration. The phenomenon of summer hibernation plays a very important role, as it helps the fish to survive outside of the water during dry periods or when the temperature is too high.

For example, in Africa, there is fish that turns into mud, thus creating a cocoon, and in a state of complete rest is there up to several months, until habitat conditions become suitable again. It is worth noting that aquarium fish rarely resort to such methods.

A couple of interesting facts about the dream of "wild" fish

In nature, these underwater inhabitants slumber differently:

  • lying belly or sideways on the bottom, like cod;
  • or up belly and upside down in the water, like a herring;
  • or buried in the sand, like a flounder; or wrapped in mucus like a blanket, like a parrot fish.

The hardest thing to sleep is cartilaginous fish, especially sharks.

  • They do not have a swim bladder, therefore, they cannot hang in the water, as they immediately sink to the bottom without movement.
  • And they cannot lie on the bottom either, since they have not gills, but gill slits, in which water will not get into without movement, and the fish will simply suffocate.

What to do? Here's what:

  • some sharks adapted to sleep in places with a bottom current, constantly opening and closing their mouths for the movement of water around the gill slits;
  • other species have sprinklers for this purpose (special gill openings located behind the eyes);
  • and still others do sleep on the go. Their brain rests at this time, and the spinal cord regulates the swimming muscles.
In conclusion, we note that if you want to see how your fish sleep in an aquarium, suddenly turn on the light at night. And for a few moments it will be possible to see how they lie belly on the bottom or on the plants with little or no movement. This is the "fish" dream.

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Fish sleep in the avkarium - create sleeping conditions

If a person has aquarium fish, he can constantly watch them awake. Waking up in the morning and falling asleep at night, people see how they slowly swim around the aquarium. But did anyone think about what they do at night? All the inhabitants of the planet need to rest and fish is no exception. But how do you know the fish are sleeping, because their eyes are constantly open?

"Fish" dream and everything connected with it

Thinking or speaking of a dream, man represents the natural physiological process of the body. When it is the brain does not respond to any minor environmental factors, there is practically no reaction. This phenomenon is also characteristic of birds, insects, mammals and fish.

The third part of his life a person spends in a dream and this is a well-known fact. For such a short period of time a person completely relaxes. During sleep, the muscles are completely relaxed, the heart rate and breathing decrease. This state of the body can be called a period of inaction.

Fish, due to their physiology, are different from the rest of the planet. From this we can conclude that their sleep occurs in a slightly different way.

  1. They can not be 100% off during sleep. It affects their habitat.
  2. In an aquarium or an open pond, an unconscious state does not occur in fish. To some extent, they continue to perceive the world around them even during their rest.
  3. Brain activity in a relaxed state does not change.

According to the above statements, we can conclude that the inhabitants of water bodies do not fall into a deep sleep.

From belonging to a particular type depends on how the fish sleep. Active during the day are fixed at night and vice versa. If the fish is small, it tries to hide in an inconspicuous place during the daytime. When night falls, she comes to life and is looking for something to profit.

How to recognize a sleeping fish

Even if a representative of the water depths envelops sleep, she cannot close her eyes. Fish have no eyelids, so water always cleans the eyes. But such a feature of the eyes does not interfere with their normal rest. It is dark enough at night to quietly enjoy the rest. During the day, the fish chooses quiet places, which are penetrated by the minimum amount of light.

The sleeping representative of the marine fauna simply lies on the water, and the current at this time continues to wash the gills. Some fish try to cling to the leaves and branches of plants. Those who prefer to rest during the day choose a shade from large plants. Others like people lie sideways or belly down to the bottom. The rest prefer to stay in the water column. In the aquarium, its sleeping inhabitants drift and at the same time do not create any movement. The only thing that can be noticed at the same time is a barely visible swaying of the tail and fins. But as soon as the fish felt any influence from the environment, it returns to its normal state with lightning speed. Thus, the fish will be able to save their lives and get away from predators.

Sleepless Night Hunters

Professional fishermen are well aware that catfish or burbot do not sleep at night. They are predators and feed themselves when the sun is hiding. During the day, they gain strength, and at night they go hunting, while moving completely silently. But even these fish love to "arrange" a rest during the day.

An interesting fact is that dolphins never fall asleep. The current mammals were once attributed to fish. Dolphin hemispheres turn off for a while alternately. The first 6 hours and the second - also 6. The remaining time is both in waking state. This natural physiology allows them to always be in a state of activity, and in case of danger to escape from predators.

Favorite places for sleeping fish

During rest, most cold-blooded people remain motionless. They like to sleep in the bottom area. This behavior is characteristic of the majority of large species that live in rivers and lakes. Many argue that all aquatic residents sleep at the bottom, but this is not entirely correct. Ocean fish even during sleep continues to move. This applies to tuna and sharks. This phenomenon is due to the fact that the water all the time should wash their gills. This is a guarantee that they will not die from suffocation. That is why the tuna falls on the water against the stream and rests while continuing to swim.

Sharks do not have a bubble at all. This fact only confirms that these fish must always be in motion. Otherwise, the predator will sink to the bottom during sleep and, in the end, it will simply drown. It sounds funny, but it's true. In addition, predators do not have special covers on the gills. Water can enter and wash the gills only while driving. The same applies to stingrays. Unlike bony fish, constant movement is, in some way, their salvation. To survive, you need to constantly go somewhere to swim.

Why it is so important to study the characteristics of sleep in fish

For some, it’s just a desire to satisfy their own curiosity. How to sleep fish, you need to know first of all the owners of aquariums. This knowledge will be useful in providing suitable living conditions. As well as people, they do not like when their peace is disturbed. And some suffer from insomnia. Therefore, in order to ensure maximum comfort for the fish, it is important to observe several points:

  • before buying an aquarium, think about the accessories that will be in it;
  • there must be enough space in the aquarium to hide;
  • fish should be selected so that everyone rested at the same time of day;
  • At night, the light in the aquarium is better to extinguish.

Remembering that the fish can "take a nap" in the afternoon, in the aquarium should be overgrown, in which they can hide. In the aquarium should be polyps and interesting algae. You also need to take care that the filling of the aquarium does not seem empty and uninteresting to the fish. In the shops you can find a huge number of interesting figures, up to the imitation of sinking ships.

Making sure that the fish are sleeping, and knowing how it looks like this, you can create a comfortable environment for your pets.

Do aquarium fish sleep?

Ewa sonnet

Can you sleep with your eyes open? No, you definitely need to close your eyelids to fall asleep. Therefore, fish do not sleep like we do. They have no eyelids that they could omit. But with the onset of darkness, the fish also rest. Some of them even lie on the side. Most fish rest calmly, which is similar to human sleep. It’s like when people sleep, but they don’t cover their ears. Some fish rest during the night and feed during the day; others rest during the day and hunt at night.

Uliana Trempolec

Of course, aquarium fish and all other fish sleep. Somehow pay attention to the aquarium fish at night, they hang in a dark place and fall asleep, do not try to wake them abruptly, they can be stressful !! ! Here SOMIKI, for example, they sleep during the day, and at night swim out of a dark place (snag, stone house).
They do not sleep like we are not moving, but they hang in the same place and move their fins so as not to roll over to the top with a belly and not die! ! And they sleep with their eyes open, since they have no eyelids that would close their eyes! !

How do fish sleep?


Can you sleep with your eyes open? No, you definitely need to close your eyelids to fall asleep. Therefore, fish do not sleep like we do. They have no eyelids that they could omit. But with the onset of darkness, the fish also rest. Some of them even lie on the side.
There are some similarities between the eyes of a fish and a man. But there are differences due to the fact that the person lives in the air, and the fish in the water. Like humans, fish have an iris surrounding the pupil. In most fish, the pupil does not change its size.
This means that it does not taper from the bright light and does not expand in the dark as it does in the human eye. Therefore, the fish can not stand the bright light, it can become blind from nothing. Fish cannot reduce the luminous flux passing through the pupil, as we do. Although there are some fish whose pupils may narrow. By the way, fish have no tears, because there are no tears. Their eyes are wet from the environment.
Most fish eyes are located on both sides of the head. Each eye of the fish sees the image only on one side. Therefore, fish have a large field of view from both sides, much more human. They can see in front of them, behind themselves, above and below. And just before the nose, the fish can focus both eyes on the same object.
Experiments have proven that some fish can distinguish colors. They can distinguish between red and green, probably blue and yellow. But few species of fish were studied. Therefore, it is impossible to conclude that all fish distinguish colors. There are big differences between fish species.

Fanis Khairullin

Do not be deceived by the fact that the eyes of the fish are always open: these living creatures also love to sleep at night and even take a nap in the morning.
Can fish sleep? For a long time, scientists puzzled over this issue, but the results of a recent study showed that after a hectic night, fish like to take a nap.
Zebra danios (Danio rerio), like most other species of fish, do not have eyelids, so it is difficult to establish what they are doing in a passive state - they sleep or just rest.
But now, researchers have been able to prove not only the fact that the fish are sleeping, but also that these living creatures can suffer from insomnia, and also difficult to endure the forced wakefulness.
Regularly disturbing the peace of the fish of this species common in aquariums (a weak electric shock was used for this), the scientists were able to make them stay awake all night. And what did it turn out? Fish that have had a restless night, try to sleep off at the first opportunity.
Some of the individuals on which the experiment was carried out were carriers of a mutant gene that affects the sensitivity of the nervous system to hypocretins, hormonal substances that help fight sleep. The lack of hypocretins in the human body is considered the cause of narcolepsy.
Zebra danios with a mutant gene suffered from insomnia; it was found that they were able to sleep 30% less time than their counterparts with a normal gene. "Fish that are insensitive to hypocretins, sleep briefly and intermittently in the dark," the researchers reported in the online journal PLoS Biology.
Thanks to the study, scientists have learned more about the functions of molecules that regulate sleep. They hope that further experiments with zebra danios selected for experiments due to the similarity of their central nervous system with the corresponding organs of mammals will help penetrate into the mechanisms of sleep disorders in humans.
“Sleep disorders are widespread, but we don’t understand their mechanisms. In addition, there are a lot of hypotheses about how and why the brain goes into sleep. the researchers.
The fish was monitored by a team of scientists from the USA and France. It was found that when the fish fall asleep, their tail fins bend down and the fish themselves stay either on the surface of the water or at the bottom of the aquarium.

Do fish sleep? How? Eyes close?


Sleep is also necessary for fish, like other animals. Fish that hunt during the day sleep at night (minnows), fish that are active at night, usually sleep during the day (burbot). The position of the body during sleep in different fish can be different. Cod lies motionless on the bottom, on the side or on the belly, herring is in the water column, belly up, sometimes with its tail or head, flounder buried in the sand. For sleeping, many fish use quiet, secluded places, stopping among the vegetation, behind stones. In general, everyone sleeps as he wants.
fish do not sleep like we do. They have no eyelids that they could omit. But with the onset of darkness, the fish also rest. Some of them even lie on the side.
There are some similarities between the eyes of a fish and a human. But there are differences due to the fact that the person lives in the air, and the fish in the water. Like humans, fish have an iris surrounding the pupil. In most fish, the pupil does not change its size.
This means that it does not taper from the bright light and does not expand in the dark as it does in the human eye. Поэтому рыба не выносит яркого света, она может ослепнуть от не-го. Рыба не может уменьшить световой поток, проходящий через зрачок, как это делаем мы. Хотя существуют некоторые рыбы, зрачки кото-рых могут сужаться. Между прочим, у рыб не бы-вает слез, потому что отсутствуют слезные желе-зы. Их глаза влажные от окружающей среды.

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Cuba Clear blue water, sandy islands and palm trees, fancy corals, flocks of brightly colored fish, mysterious grottoes with sleeping sharks.
Cuba is a paradise for fishermen, scuba divers, and underwater photographers. About 900 species of animals and fish are found in the fresh and saline waters of the island, of which we call dolphins, barracuda, pelamid, tuna, stingray, groupers, moray eels, lobsters, angelfish, mackerel and sharks. The latter, to put it bluntly, never caused divers any trouble. Meetings with them are extremely rare. Warm waters are especially fond of jellyfish, octopus and sea turtles.
Oysters and lobster - industrial and tourist fishery objects. The seabed is dotted with a wide variety of shells. At one time, Soviet specialists were very fond of catching and making objects of memory of Cuba from lobsters, ball fish, sea shells, black coral and even crocodiles. Although, I must say, their export outside the country is prohibited. However, all exported, do not just abuse.
In Cuba, it is officially forbidden to hunt fish with a gun. But agreeing through a guide or directly with the crew of the boat is not a particular problem. Officially, you have a boat trip, but it’s better not to stick your sea guns before sailing.
Diving in Cuba is at the initial stage of its development. The number of diving centers is not large and their equipment may not be enough, therefore it is recommended to have your equipment.
For lovers of night dives, information that night dives on the Atlantic coast of Cuba are allowed only from the shore, but not from the bot will be useful. This is due to the proximity of the US state of Florida and the possibility of illegal border crossing.
Huge reefs, located along the coast almost continuous shaft, called barrier. In Cuba, barrier reefs are particularly well developed along the northern coast. The coral barrier follows from Cape San Antonio to Cape Maisi, now approaching the coast, now moving away from it. The length of this great barrier is more than two thousand kilometers. It is second only to the Great Barrier Reef of Australia, and in the Atlantic Ocean there are no rivals. In those places where the coral barrier merges with the coast, the reef becomes coastal or bordering. The entire southeastern coast of Cuba from Cape Maisi to Cape Caboz is covered by a fringing reef. On the south-west coast of Cuba from Cape Guanal to Cape San Antonio is also developed a fringing reef. The total length of the coral coast of Cuba is almost four thousand kilometers.
Resorts The most famous resort area of ​​Cuba - Varadero is located 140 km. from Havana on the Atlantic coast. Twenty kilometers of the finest white sand and azure blue ocean waters. Varadero is a typical resort town with many hotels, clubs, restaurants and discos. Tourists are guaranteed a great tan, entertainment around the clock, as well as the opportunity to engage in water sports and diving. The beaches of Varoadero are protected from the sea by the largest coral reef in the Caribbean. Barrier Reef Varadero is rich in marine life and many wonderful diving sites. Here are the sunken ship "Neptune" - an ideal object for photo and video because of the shallow depth (only 10 meters) and the associated good light.
In the area of ​​Clara Boyas, at a depth of 20 meters, massive coral heads with wide tunnels attracting 3 to 4 scuba divers.
The most attractive dive sites:
Playa Coral Depth 20 m. Coral reef can be reached from the beach. About 30 species of corals form canals, passages and caves, many of which go to the ocean. Cueva de Saturno Depth 20 m. Underground gallery about 150 m long and more than 5 meters high, filled with sea and fresh water at the same time, with stalactites and stalagmites. An ideal place for lovers of speleology.
Great opportunity to see specific cave dwellers - shrimps and blind p


They are asleep, so I have goldfish and red hats, they just freeze in one place, not moving at all, closer to the bottom of the aquarium and so "hang", of course they don’t close their eyes, because there is nothing to close, not the eyelids, but in general funny, interesting to watch them.

Pavel Makhov

For lower organisms, the absence of eyelids is quite typical ... So, we would be happy to close it, but there is nothing ... In general, they sleep. This is the greatest difficulty for sharks - these fish do not have gill covers (they have cracks), so the shark has to constantly move to breathe ... However, according to the observation of J. Cousteau, coastal sharks sleep in cracks in which there is a flow (ventilator of the gills) .

Pink Flamingo

All fish at night behave differently. Some of them are just starting active activities, such as eels, others freeze and sleep, while they can be gently touched, then they wake up and move. For example, ordinary perches always rest with their belly on some kind of support — be it solid bottom areas, some fragments on the bottom, any automobile tires and other large trash, preferring objects with cavities inside — you will shine a flashlight into some thick pipe wallowing at the bottom, there necessarily sleep perch. Pikes prefer to sleep hovering diagonally, head slightly up in some fork of reeds or any other plants, or pressed sideways to some pile. Bleak always sleep in the water column, almost never lying on the bottom and glow brightly when illuminated by their lantern. Some fish (mostly sea, from freshwater-seen only perch) during sleep release a large amount of mucus, a little cloud surrounding them. This cloud in the direction of the light of the lantern glows like an aura, creating the illusion of increasing the size of the fish — they say it is necessary for a healthy sleep, and you should not wake and frighten such fish, otherwise they have stress from this ... In general, it is better not to wake the fish and not a dream, and then suddenly they will have nightmares ...

Why do goldfish sit at the bottom of the aquarium and how they sleep. Are they healthy? and WHAT to do with them to activate them?


Goldfish are considered to be cold-water, as they easily tolerate a decrease in temperature, but they are most playful at a temperature of 22-24 degrees. Sharp temperature fluctuations are unacceptable! For ordinary goldfish, the water temperature in an aquarium can vary from 8 to 30 degrees, the optimum is 15–20 degrees, ornamental rocks are much heat-loving; The chemical composition of the water is not important. Goldfish (long-bodied, contained in pools and ponds) tolerate a decrease in temperature to 0 degrees Celsius and can winter under ice. It should be borne in mind that with a prolonged decrease in temperature, the fish may become more susceptible to various diseases, and warming of water leads to a decrease in the content of oxygen dissolved in it, from which cold-water fish suffer greatly, start to eat little and become exhausted. In hot weather, daily water changes prevent overheating of the aquarium.
For goldfish, aeration of water is obligatory, in which water is enriched with oxygen both from the surface of air bubbles formed by the nebulizer and from the surface of water. As a result of the circulation of water caused by the flow of bubbles, the oxygen-rich upper layers are mixed with depleted lower layers. In addition, the circulation is also useful in that it mixes relatively warm upper layers with cooler bottom layers, thus creating uniform temperature conditions inside the aquarium. If your fish are constantly at the surface of the water and swallow air, then this is the first sign of oxygen deficiency. It is necessary, or to change the water / part of the water, or to strengthen the aeration, or to plant fish.
The presence of a filter in aquariums with goldfish is also a necessary condition, as mobile and voracious fish, taking food from the ground and constantly rummaging in it, pollute the water. The power of the aeration compressor and / or filter (measured by the amount of distilled water in liters over a certain period of time) is selected depending on the size (volume) of the aquarium. The average is the power at which an compressor can pump over the entire volume of water in an aquarium in an hour. After several months of running an aquarium, you will be able to accurately set the power required in your case. If one type of filter is insufficient, you can use a combination of filters, a large selection of which is presented on the market of equipment for aquariums.
By the way, if your fish live with you for a long time then it can be from old age. I once had a telescope and it also lay at the bottom, but believe me, lying at the bottom of the nickname did not lead him to live for 3 years, if not more, and died safely from old age.

How a cockerel fish eats and sleeps