Iron is important in promoting the growth of macro- and other calcareous algae. Although typically contained in most salt mixes, iron is rapidly depleted in the average reef system, either through normal biological processes (being used up by the inhabitants) or by being removed through protein skimming. By dosing regularly with ECO Iron macroalgae in refugium filters are less likely to reproduce sexually, helping to prevent any water quality issues in the main system. ECO Iron has been specially formulated to replenish and then maintain the iron concentration at a level that will ensure the optimal growth and health of macro- and other calcareous algae in the reef aquarium.ECO Iron helps increase green coloration in corals that use this spectrum. It contains no fertilizers, and will thus not cause outbreaks of hair algae or other undesirable organisms.