Why is Cameron angry when he sees Tova in "High and Dry" and what does he do?

When Cameron comes to the aquarium, he is very angry. He tells Tova that he is angry at Ethan, his friends in Modesto had a baby and his band is done, and that he learned that the man he thought was his father is not. He takes the class ring that he found with his mother's things and throws it in the wolf eels' tank. Then he tells Tova that he is going back to California.