It's best to keep crabs in a water tank. Crabs are easily frightened and afraid of light. If you really can't raise crabs in a fish tank, you'd better choose a bigger one, and the bottom sand and aquatic plants must be put. The life span of river crabs is generally only 2-3 years, and in some cases the longest can live for four years. It is best to be a slightly alkaline water body, with a PH value of 7.5-8.5, suitable growth water temperature 18-30 degrees Celsius, and the best growth water temperature. The requirement for dissolved oxygen in water is above 5 mg/L, and clear tap water is the best. Like fish, river crabs are warm animals, and their body temperature rises and falls with the rise and fall of water temperature. It is omnivorous, mainly animals, and likes to eat dead fish, rotten shrimp, rotten animal carcasses, organic debris, small snails, clams, insects and larvae. In general, river crabs are more likely to pounce on plant bait than animal bait. In natural life, the proportion of food is often dominated by plant bait, mostly coastal plant debris, filamentous algae, willow weeds, black algae, duckweed and so on. And you can also eat artificially fed vegetables, tender grass, shredded potatoes, whole grains, bran and the like. Artificial compound feed, animal offal, etc. I like eating, too. Eriocheir sinensis has strong digestive ability, gluttony and large appetite, and the nutrients produced after satiety are stored and accumulated in the liver. Crabs have a strong ability to starve to death, and they will not starve to death if they don't eat for ten days and a half. Temperature has a direct effect on the feeding of Eriocheir sinensis. When the water temperature is above 15℃, the food in the stomach is full, and when the water temperature is around 10℃, the food in the stomach is half full. When the water temperature is lower than 10℃, the metabolic function is weak, so they seldom eat, and they don't eat during the winter in hibernating caves. In addition, escape prevention facilities must be made in breeding. Finally, I suggest you choose a suitable place to release it. A crab is so lonely!