Hutt Lagoon is a pink lake, a salt lake with a red or pink hue due to the presence of the carotenoid-producing algae Dunaliella salina, a source of ß-carotene, a food-colouring agent and source of vitamin A. The lagoon contains the world's largest microalgae production plant, a 250 hectares series of artificial ponds used to farm Dunaliella salina.