The Seachem Discus Trace is a scientifically formulated watter additive that has been created to supply a broad range of trace elements that guarantee that proper health and development of sensitive Discus fish. Unlike terrestrial animals, fish obtain essential nutrients and minerals from both their food and from the water column, which makes it all the more important to have the proper nutritional parameters within the aquarium. These incredibly important trace elements are often depleted naturally through utilization, oxidation and precipitation, and because of this it is critical to restore them on a regular basis. Seachem Discus Trace only contains elements that have been scientifically demonstrated to show benefit to Discus fish, cutting out any unnecessary ingredients from the product. Where many fish tolerate the use of salt for therapeutic measures, Discus species and many live plants cannot handle this elevated level of sodium, so this top of the line solution contains zero sodium to ensure optimal efficacy and safety.