Strontium is one of those elements seeming to be important for the growth of stony corals. Though up to now this has not been scientifically verified, numerous thriving reef tanks with regular strontium supplementation all around the world prove that stony corals and giant clams develop better under a regular strontium supplementation. KORALvit S enables you to replace the lost strontium and keep the strontium level on natural values.