For use in saltwater fish tanks and reef tanks, The counter-current Protein Skimmers help prevent toxic tank syndrome by by removing proteins and other organics before they turn into nitrogen compounds or other toxins that may be harmful to aquarium inhabitants, Throough ADSORPTION, protein and other organic compounds in the water from a coating around bubbles as they rise to the top, The resulting foam floods over the top of the foam-riser tube and is captured in the collection cup before it can re-enter the aquarium, Packaging Boxed, SKU: RYLHC2931