Skip Navigation Website Accessibility


Is best used in a media reactor for maximum performance, which is the standard for all granular ferric oxides.  Simplicity GFO can also be used in a media bag but will not be as effective compared to a filter media reactor. 

In saltwater aquariums, GFO is generally regarded as a very safe and efficient way to reduce phosphates and silicates from the water. Maintaining low phosphate levels will help prevent algae outbreaks and control algae growth in reef tanks. In addition to reducing phosphate, GFO also absorbs fluoride, molybdenum, selenium, antimony, arsenic and more.



  • Binds Phosphate (po4) from the water
  • Helps with coral growth and coloration in reef tanks
  • Can be used in a filter media reactor or media bags
  • Will help control and prohibit algae growth by removing phosphate out of the water
  • Use only 1/2 cup per 25 gallons