Intensify Red & Pink Coral Colour. Reef Essential® Bio-Kalium™ is designed to provide ionic & complexed potassium as well as boron to help intensify red & pink coral colour. Potassium helps to transport nutrients and when used with boron aids in the production of aragonite. This product must be used alongside our Reef Essential® Bio-Enhance™, Reef Essential® Bio-Metals™ & Reef Essential® Bio-Gen™ supplements as together they will provide the required biomolecules, major, minor and trace colouring elements. If wanting to enhance coral bone growth & density we recommend our Aragonite Enhancers™. Recommended potassium concentration = 375-400ppm.