Inland Seas Biotrace one step trace element and vitamin supplement is used to replace trace elements and vitamins that are rapidly removed by plant and animal growth, protein skimming, activated carbon, and ozone use. Biotrace contains Strontium, Iron, Iodine, Molybdenum, Vitamin C and B12, as well as other trace elements, vitamins, and amino acids that promote healthy growth and colorful pigmentation in marine fish, pink and purple coralline algae, calcareous and macro algae, soft and stony corals, tridacna clams, and other invertebrates found in captive marine systems. Biotrace Is safe for use in systems using ozone.