A poem or famous saying describing fish culture in a fish tank
The water level is based on the fact that fish are not easy to jump out of the tank. Because the goldfish is beautiful, graceful and not good at jumping, the water level should be 10- 15 cm away from the tank edge. Because the more water, the more oxygen, the wider the sea. This is a famous saying. We can't be satisfied, but we can make full use of the existing conditions, right?