Essential trace elements are minerals, which are needed in small amounts by the aquarium inhabitans for active biological processes. Tropic Marin Pro-Coral A- Elements provides these minerals in an optimized formula designed to replace depletion from the consumption by corals and invertebrates.Tropic Marin Pro-Coral A- Elements+ contains: bromine, fluorine, iodine, lithium, molybdenum, selenium and vanadium in anionic form+ essential anionic and cationic trace element supplements in a liquid form+ a complete profile of the essential trace elements with only two solutions+ supports ideal growth and natural coloration of corals and invertebrates+ no bleaching of the coral due to lack of trace elements+ easy to apply - suitable both for manual dosing and for dosing pumpsUse of Tropic Marin Pro-Coral A- Elements:For a complete trace elements supply, we recommend the use of both trace element solutions (A- Elements, K+ Elements): Add 1 ml trace elements of each solution per 100 l/25 US-Gal.