1. Green puffer fish belongs to marine fish, but it can be raised in fresh water. This fish has sharp teeth and will attack other small fish. When encountering bigger fish or danger, its body will expand to scare off the enemy.

2. Salt can be added to the jar, and its color, pattern and spots vary greatly. Because it has teeth, it can bite small fish, choose to keep it alone, like to eat snails, and its eating habits are miscellaneous. Fish turn black when they are in poor health.