You are getting sheets of high quality "Nori" seaweed. The nutritional value of nori, being high in carbohydrates, protein, vitamins, and especially minerals, they began using it to feed their saltwater herbivores.
It is ideal for feeding tangs and surgeonfishes, some angelfish and blenny species, as well as many other types of algae eaters like hermit crabs and snails.
Nori seaweed draws an extraordinary wealth of mineral elements from the sea that can account for up to 36% of its dry mass.
These nutrients include sodium, magnesium, potassium, iodine, zinc, Beta carotene, vitamin A, vitamin B complex, vitamin C, and calcium.