Goldfish, like all other fish, have no eyelids, so it is impossible to close your eyes at any time, and sleeping is no exception. The fish usually find a shaded place when they sleep, usually hiding in some shelters in the fish tank, such as small rockery or water grass, so that they can sleep to avoid the attack of other fish.
1, hide in the dark: Most fish sleep like goldfish, will hide in the dark, some of them hide in water plants, some hide behind rocks, and some will hide in narrow crevices, so that they can avoid other aquatic animals. Especially the attack and predation of various natural enemies.
2. Secrete bubbles: In tropical and subtropical waters, there is a kind of parrotfish. At dusk, this kind of fish secretes mucus on its body surface. It wraps itself with this layer of mucus. At the same time, it opens a mouth in the front and a mouth in the back to facilitate the inflow and outflow of water. In this way, the fish can sleep at ease without worrying about being attacked.
3. Hide in the sand: Because of their size, some fish can't escape from water plants and stones, so they can only hide in the sand when they sleep, and then come out of it when they wake up.
4, while swimming while sleeping: In the ocean there are some fish, must be in the process of swimming to breathe, once stopped can not live, so when sleeping will also sleep while swimming, such as tuna, sharks, etc., are so.
