Be confident in your purchase we're an Authorized ATI Dealer. How cool is that?!?!? Iodine is one of the most important elements in the marine aquarium. Among other things, it is essential for the thyroid function of fish and is enriched by many other organisms in the tissue. These organisms include i.a. Corals, sponges, shells and algae. The function of the iodine in the individual organ species has not been sufficiently investigated yet, but there is a higher iodine consumption in strongly illuminated aquariums. Iodine is also suspected to intensify the blue coloration of corals of the genus Acropora. Iodine is consumed relatively quickly in the aquarium. Therefore, the iodine concentration should be checked regularly in the laboratory. Targeted supplementation works best with our ultra pure iodine supplement. 1 ml of the supplement increases the iodine concentration of 100 liters by 100 ?g/l Free from EDTA or other accumulative chelators.