E.S.V.'s Bromide Fluoride Supplement conservatively adds important major ions which can be depleted via calcification and biological organic synthesis. Fluoride is concentrated in coral skeleton and may play an important role in calcification. Some marine organisms use bromide to synthesize organic anti-microbial compounds which may enhance their ability to resist disease. Bromide, like iodide, is also highly concentrated in many marine algae. Any export of these algae from the system, such as harvesting algae filters and photosynthetic particulate removal via protein skimming, could result in depletion of bromide.