1. How to raise domestic starfish

Domestic starfish should pay attention to water quality, ingredients and temperature. First of all, in terms of water quality, starfish are very sensitive to ammonia and nitrate, so the lower the nitrate and phosphate, the better; If the water quality deteriorates, starfish may be infected by bacteria, resulting in sores or lesions on the skin. Secondly, in terms of ingredients, starfish are carnivorous animals, which can feed on various invertebrates or slow-moving marine animals; Mainly eat shellfish, crustaceans, polychaetes and even fish; Such as oysters, abalone, sea cucumbers, crabs and scallops. Most starfish (except a large number of carnivorous fish) eat boiled spinach and cabbage, and feed them every two to three days. When feeding, put the food next to the starfish, and the starfish will run to eat if they are hungry. Finally, in terms of temperature, the temperature of domestic starfish is kept at 26-28℃ and the pH is between 8. and 8.3. In addition, it is best to raise starfish with rock walls, corals, living stones, caves, corners and broken corals or fine sand substrates as AIDS.

2. Species of starfish

Starfish are mainly divided into three categories, namely, the banded starfish, the echinodermata starfish, and the echinodermata starfish. Obvious band purpose: The wrist has two rows of obvious edge plates, no skin gills, lives on the soft seabed, has two rows of tube feet and no sucker, and is arranged in two rows in the band ditch, which is beneficial to burrowing or crawling in the sediment. Most deep-sea starfish belong to this purpose, such as Acer starfish, which filter their food with cilia. Echinodes: the marginal plate is very small, and the forked spines are simple or lacking. There are clusters of spines, and there are suction cups at the foot of the tube, but forked spines are rare. Camel petrels are common on the rocky seabed in Europe. In the north, the genus Heliocephalus and the genus Heliocephalus have many short wrists with wide body plates, while the ratchet starfish has 15 wrists. Forceps: There are two-valved forked spines with long stalks, which have protective or feeding functions. Common species that feed on bivalves in shallow water include the red starship distributed in northern Europe and the spiny starship from the Bering Sea to the Korean Peninsula. The short-spined bean starfish on the west coast of North America is 65 cm long and is one of the largest starfish in the world, feeding on sand money sea urchins and so on. The multi-wrist sunflower starfish from Alaska to California has 15-24 wrists. There are up to 5 wrists of the genus Justarfish in China and America. ?

3. Starfish's predation method

First of all, most starfish have long flexible wrists and sucker on the tube foot, and most of them feed on bivalves. When they feed, their bodies are on the shell, and their wrists are sucked on both sides of the shell. Due to the vacuum effect of the sucker at the end of the tube foot, the pulling force is enough to open the shell mouth of bivalves, and the starfish immediately turns out the spouted stomach and inserts it into the shell mouth, and secretes digestive enzymes until the obturator muscle and viscera.

Secondly, some species with short wrists and no sucker on the tube feet feed on smaller animals, such as small crustaceans. When feeding, the whole food is swallowed and digested in the stomach instead of in vitro.

finally, the species living in the deep sea feed by cilia filtration, and the sediment and organic matter falling on the body surface are swept into the step ditch by cilia action to form food rope, and then sent into the mouth, such as Acer starfish. Another example is the chicken-claw starfish, which has cilia in the gastric caecum, and relies on the movement of cilia to help suck food into the stomach.

References

Various starfish. Sohu.com [reference time: March 9, 218]

What food do starfish eat. Qiannong.com [reference time: March 9, 218]