Do fish have eyelids Do fish have eyelids and why do fish not have eyelids

Of course not! So when the fish sleeps, it is like sleeping with their eyes open.

Fish do not have eyelids, the main function of eyelids is to moisten the eyes, and at the same time provide protection, fish live in water, so they do not need eyelids to moisten the eyes, a few fish have an instantaneous membrane similar to the eyelids, which can play a role in protecting the eyes. These animals generally have fins, which are divided into pectoral fins, pelvic fins, anal fins, dorsal fins, and caudal fins, which allow the fish to swim and maintain their balance at the same time.

Fish do not have eyelids. The eyelids, also known as the eyelids, have two functions, one is to protect the eyes, and the other is to moisten the eyes by turning them. Fish themselves live in water and do not need to moisten their eyes, so they do not need eyelids much.

However, some sharks have eyelid-like membranes or folds that allow them to protect their eyes when hunting.

1. Pectoral fin: The pectoral fin grows behind the gill cover, and for fish, the role is similar to the forelimbs of land animals, which can play a role in balancing and mastering the direction when it swims, and can maintain balance when it stops. If the speed of swimming is slow, the pectoral fin acts like a paddle and is attached to the body when moving at height to be able to slow down and brake.

2. Pelvic fin: If the pectoral fin is the forelimb, then the pelvic fin is similar to the hind limb of a terrestrial animal for fish, which is used to assist the dorsal fin and anal fin to maintain balance, and at the same time help the fish to rise and fall, as well as change direction. Usually the pelvic fins are not born in a fixed position, some are ventral, some are in front of the pectoral fins, and some feed the larynx between the gill covers.

3. Anal fin: The role of the anal fin can coordinate the fins of each fish, if not, the body of the fish will shake slightly.

4. Dorsal fin: The dorsal fin can keep the fish upright, which plays an extremely critical role in balance, and it is easy to roll over if you lose it. In addition, for some fish with longer body lengths, the dorsal fin can also play a role in propelling forward.

5. Tail fin: The tail fin is particularly important for fish, which can not only determine the direction of movement, but also provide power.

Fish don't have eyelids because they don't need eyelids. The eyelids have two functions for terrestrial animals, one is to moisten the eyeballs and the other is to protect the eyes, and for fish, since they live in water, they do not need eyelids to moisten the eyes.

And there is no sand and dust in the water to get into the eyes, so there is no need for eyelids to protect them. However, some sharks have eye-like membranes that cover their eyes when they hunt.

Summary. The main reason for the upper and lower eyes of the fish is the environment, and the fish tank will generally raise the tank seat to facilitate viewing. The visible surface of the fish tank body, including the front and back, left and right, above and the bottom of the tank, usually the moving things on the ground will always attract the attention of the Arowana, and then produce actions such as looking for things in the tank, and over time, the phenomenon of downward vision will naturally appear, and cause the accumulation of fat in the eye socket.

The main reason for the upper and lower eyes of the fish is the environment, and the fish tank will generally raise the tank seat to facilitate viewing. The visible surface of the fish tank body, including the front and back, left and right, above and the bottom of the tank, usually the moving things on the ground will always attract the attention of the Arowana, and then produce actions such as looking for things in the tank, and over time, the phenomenon of downward vision will naturally appear, and cause the accumulation of fat in the eye socket.

Lay bottom sand at the bottom of the tank to avoid the bottom of the tank reflecting the Arowana's own shadow, chasing the shadow of the bottom of the tank, causing downward vision and forming upper and lower eyes.

Summary. Dear Hello I'm glad to answer the reasons for the fish's upper and lower eyes: First, the physiological structure of the fish makes it possible for them to have a cross blind spot in front of their eyes, and the circular container is not visible in front of the fish, so they swim all the way to the surface of the water.

The second is that the lone glass refracts light into the water, which will cause damage to the vision of the fish, resulting in an increase in the internal pressure of the fish's eyes, and eventually the death of the swim bladder. The third is that the small round tank does not have a filtration system, the water is not changed frequently, and the water quality deteriorates, resulting in fish eye lesions.

Dear Hello I'm glad to answer the reasons for the fish's upper and lower eyes: First, the physiological structure of the fish makes it possible for them to have a cross blind spot in front of their eyes, and the circular container is not visible in front of the fish, so they swim all the way to the surface of the water. The second is that the lone glass refracts light into the water, which will cause damage to the vision of the fish, resulting in an increase in the internal pressure of the fish's eyes, and eventually the death of the swim bladder.

The third is that the small round tank does not have a filtration system, the water is not changed frequently, and the water quality deteriorates, resulting in fish eye lesions.

Pro, the main reason for the fish eyes up and down is the environment, and the general fish tank will raise the tank seat to facilitate viewing. The visible surface of the fish tank body, including the front and back, left and right, above and bottom of the tank, usually the moving things on the ground will always attract the attention of the Arowana, and then produce actions such as looking for things in the tank, and over time, the phenomenon of looking down will naturally appear, and cause the accumulation of fat in the eye sockets. There is a way to delay the downward vision of the eyes, and the first thing to do is to improve the breeding environment

1) Lay the bottom of the tank with bottom sand to avoid the bottom of the tank reflecting the image of the Arowana itself, chasing the shadow of the bottom of the tank, causing the downward view (2) The visible surface of the left, right and back of the fish tank is covered with opaque background paper, and the visible surface and a downward view surface are retained. (3) Lower the water level by 10-15 cm, so that the Arowana can increase the visible surface on the water surface. (4) Try to feed floating fish food, including floating feed, insects or animals, and feed fish and shrimp with single and double feeding, so that fish can bite in pelagic waters.

5) Choose a two-eyed flat feeding as much as possible.

Your fish have blindfolding, most of the occurrence of blindfold is caused by poor water quality, which may be related to insufficient water change, so that the pH value of the water is too low, and all kinds of harmful bacteria in the water breed seriously, living in such water, the fish is very easy to get sick Even if the strong ornamental fish species will be invaded by harmful bacteria, suffering from blindfolding, rotten fins, rotten meat, water mold and other diseases, and the dirty water quality is not suitable for watching tropical fish.

Therefore, it is best to increase the frequency of water changes appropriately. If the condition is not severe, it usually recovers after a few water changes (you can see the recovery process: the white coat on the eyeball gets smaller and smaller until it disappears), and the water should be kept clean in the future.

Blindfold can also be treated as follows**

Soak the fish in 1% salt water.

The most popular drugs on the market include Ace Racy Eye Disease Special Drug, Ace Special Effect Drug. Use as directed.