Grander Musashi summary:

Musashi and his father move from Tokyo to the countryside, much to Musashi’s disappointment. One night, however, he comes across the fisherman Jim, and after seeing his skill is inspired to learn fishing himself. He shows a marvelous talent and takes trips with his new friends, Mio and Suguru, to many places around the world in search of incredible fish. Through fishing, Musashi comes to enjoy living amongst nature.