Ask about the eating habits of fish.

Farmers reported that when feeding grass carp, the fish ate our company's materials (pellets) in the middle and lower layers of the water, while eating other companies' materials floated on the surface to grab food. Have you ever been in a similar situation? What is the main reason for this?-- it is usually eaten on the surface of the water, probably because of the high temperature under the water-- now the temperature is low and the food intake is less exuberant. So it's not very controversial, is it?