Bettas will eat aquatic plants, but usually these plants are not their main source of food. Bettas are omnivorous fish. In the wild, they mainly feed on small aquatic insects, plankton, and benthos. When food is scarce, they will eat aquatic plants as a supplement.
Aquatic plants are rich in nutrients such as protein, carbohydrates, and cellulose, which are of certain help to the growth and health of bettas. However, the oral structure of bettas is not suitable for chewing and digesting aquatic plants, so they usually only eat them under specific conditions.