High quality phosphate and silicate removal media. It has a significantly higher absorption capacity, particularly in saltwater tanks, when compared to the normal Kolar Labs GFO. It is used to prevent and eliminate unwanted algae growth in your tank. Kolar is the exclusive distributor for Lanxess for this GFO Bayoxide ® E33HC to the aquatic industry in North America. This media is also known to be effective at removing arsinic and many heavy metals from tap and aquarium waters, without removing beneficial trace elements in saltwater.