How to keep jellyfish? What food is best to feed them
Jellyfish are beautiful marine aquatic creatures, shaped like a transparent umbrella, very beautiful. If groups of jellyfish gather together, it is surely a stunningly beautiful scene. People who have seen jellyfish may all have a question, because they have never seen a jellyfish's “mouth”, so they are very curious about what jellyfish usually eat?
How to keep jellyfish
1. Seawater aquaculture. Jellyfish are marine organisms, so they must be kept in seawater. About once a week, the water also needs to be changed for them, to avoid dust and microorganisms blocking the jellyfish and fish from receiving energy and affecting their movement speed. When changing the water, be careful not to touch the jellyfish. When adding water, do not rush; it should be slow.
2. Feeding. Jellyfish have very high requirements for food. Artemia, brine shrimp (for brine shrimp cultivation, please refer to other experiences) and other plankton are their favorites. When the digestive organs and oral cavity in the jellyfish's wings turn orange, it means the jellyfish is already full. The number of feedings and the amount given should be well controlled, and it should not be too much, because it will easily cause the water quality to deteriorate.
3. Light source. Light is an important factor for jellyfish to replenish energy. Some algae in the jellyfish body, single-celled zooxanthellae, supply the oxygen produced by their own photosynthesis to the jellyfish, while the nitrogenous waste produced by the jellyfish's metabolism is exactly provided to the single-celled zooxanthellae in its body. The relationship between the two is interdependent.
What food do jellyfish eat
1. Jellyfish are all carnivorous animals, feeding on plankton, small crustaceans, polychaetes and even small fish. Although they look beautiful and gentle, they are actually very fierce. Once they encounter prey, they never let it go easily. However, they have no respiratory organs or circulatory system, only primitive digestive organs, so captured food is immediately digested and absorbed in the coelenteron.
2. The digested nutrients rely on the beating of cilia on the walls of the circular canals to push the nutrients from the gastric cavity through the radial canals into the ring canal, and then through the direct radial canals, interradial canals, gastric cavity and mouth to expel the undigested and unabsorbed food residues from the body.
3. Jellyfish feed on plankton in the water, but in an aquarium, it is impossible to provide this water full of plankton and organic matter. Therefore, the bait is mainly brine shrimp. It is also necessary to supplement jellyfish liquid feed and seawater trace elements, and there are also seawater rotifer feeds specially for soft-bodied organisms.
Which jellyfish are highly toxic
1. Box jellyfish: Each tentacle of the box jellyfish has enough toxin to kill 50 people, and it can stop a person's heart and lung function within 3 minutes. Since 1884, at least 5567 people have died from this animal, and the mortality rate it causes is even higher than that of snakes, sharks and saltwater crocodiles.
2. Portuguese man o' war: The one that secretes fatal toxins in the Portuguese man o' war is the tiny stinging cells in the tentacles. Although the toxin secreted by a single stinging cell is negligible, the intensity of the toxin accumulated by thousands of stinging cells is not inferior to any venomous snake in the world today.
3. Sand jellyfish: The umbrella diameter of an adult sand jellyfish is 25-60 cm, with a maximum of nearly 1 m. The surface of the outer umbrella is smooth, and the mesoglea is thick and hard. Its stinging cells are highly toxic. After a human body is stung, the skin becomes red and swollen, painful and itchy, and in severe cases there may be shock, or even death.
4. Lion's mane jellyfish: The lion's mane jellyfish is an organism that can cause human death, but it rarely moves in places where humans come and go. The stinging cells on the tentacles contain venomous needles and capsules filled with venom. When the venom enters the human body, it quickly causes paralysis and death.
Is it toxic after being stung by a jellyfish
Being stung by a jellyfish is toxic. The surface of the jellyfish's tentacles and tissue around the mouth has stinging cells distributed on it. The stinging cells contain nematocysts that store venom, and can fire nematocysts to inject venom into the human or animal body, producing multiple biological toxic effects on the cardiovascular system, blood, nerves, muscles, and so on. Jellyfish toxin has lethal activity, hemolytic activity, cardiovascular toxicity, liver toxicity, neurotoxicity, enzymatic activity, and so on. After being stung, humans may experience rash, redness and swelling, itching, pain, decreased blood pressure, and even difficulty breathing, fainting, shock and death.
The world is big, and nothing is too strange. It turns out that the beautiful-looking jellyfish is also a carnivorous animal. Usually, their main prey are small fish, small shrimp and some plankton. Although it looks gentle and beautiful, it is always “ruthless and vicious” toward its prey. As long as it catches it, it will never easily let go.