Crab is relatively easy to raise, because he is not very strict about the dissolved oxygen in water, and he can live without water. If you want to raise it, you should find a glass jar and put small stones in it to simulate the living environment of crabs in the outside world. You should pay attention to the stones, and be careful that they run away. Crabs often cooperate in groups to stage a great escape, and don't add too much water. In the water, the stones are designed as reefs, and crabs like to stand on the stones on the water surface and eat. If you are partial to meat, just get it some small fish and earthworms. If these things are not clean, give the crab tofu. It also likes to eat soy products, and there is no need to change the water frequently. Be careful that the little crab does not adapt.