Fritz Aquatics Trace Elements for Fresh Water AquariumsTrace elements are not required in large quantities but are vital to the development and health of all living things. Specific trace elements including calcium, iron, magnesium, sodium, manganese, and others are part of the fundamental process of nitrification in freshwater aquariums. The lack of these critical elements can slow down or prevent nitrification resulting in elevated ammonia and nitrite levels that are harmful to fish and invertebrates.