... Feed your fish a regular diet of purple seaweed to help keep their immune system up to ... fish if not all in your aquarium will eat seaweed like butterfly fish, clown fish, engineering gobies, damsels ... and even freshwater fish. Saltwater Correct dried purple seaweed is plain and simple, just whole wild saltwater ... in vitamins A, B1, B2, B3, C, and E, iron, iodine, potassium, and trace elements. Size:21 ...