Our Coral Essentials, Coral Power Iodine is a concentrated blend of Iodine 10,000 ppm (1%) for marine aquariums. It is essential for healthy growth of both soft and hard coral as well as the promotion of healthy macroalgae growth. Iodine is also used for enhanced blue colouration in corals. Iodine is an essential element for proper cellular function and the transfer of nutrients within cells. Iodine is utilized by corals for the synthesis of pigments, which allow them to adapt to varying light conditions and provide their tissue with protection from UV radiation. Invertebrates with exoskeletons (shrimp, crabs, etc.) require iodine for exoskeleton formation as they grow. To ensure healthy coral, invertebrates and macroalgae, maintain a dosing plan as detailed below. Variances above and below the recommended dosing can be made depending on your own tank conditions and density of coral present.