Zooxanthellae are microalgae's that act as life partners with corals and clams, living withing their tissue and producing nutrients in one of Nature's most unique examples of symbiosis. The relationship between coral and zooxanthellae is so strong that often the coral cannot live without them. For the first time, live zooxanthellae by Algagen Phycopure is available for your captive reef, coral & clam saltwater aquarium. Live zooxanthellae by Algagen Phycopure is reported to help bring a stressed system back to health. Specimens that can benefit are Small Polyp Stony corals (SPS), Large Polyp Stony Corals (LPS), Soft Corals & Clams. Algagen recommends to add 1-2 capfuls per 10 gallons in a high flow area of your saltwater reef aquarium.