PURA PhosLock is the benchmark ferric hydroxide media for total phosphate removal, used in freshwater, saltwater, reef & planted aquariums all over the world to keep them clean and free from algae blooms. PhosLock permanently binds phosphates. Place it directly in a filter bag and throw it in almost any kind of filter, and replace as needed when phosphate levels rise.
For freshwater aquariums use 1 tablespoon per 50 gallons of water monthly.
For saltwater and crowded freshwater aquariums use 1 tablespoon per 25 gallons of water monthly.
For reef and planted aquariums use 1 tablespoon per 20 gallons of water.