The Kent Marine Strontium & Molybdenum supplement provides bio-available strontium for lush growth of purple, pink and green calcareous algae, snails, hard tube worms and clams. Magnesium is added to make up for deficiencies in some of the newer brands of sea salt mixesPotassium & molybdenum are added to assist the symbiotic algae growing in coral and other invertebrates tissuesWith regular use corals will open more and stay attached to their skeletons better, Phosphate & nitrate freeContains no gluconates, EDTA, or other organics to raise DOC levels, as many competing products do