Algaefix Marine is a reef-safe aquarium algaecide which controls many types of algae in marine and reef aquariums. Will not harm marine fish, corals and other invertebrates. Algaefix Marine effectively controls Green algae, “Red Slime,” and “Brown algae”. When used in salt water Algaefix marine will not harm snails, clams, scallops, shrimp, anemones, sea cucumbers, feather dusters, coralline algae, soft corals, hard corals and other invertebrates. Use weekly to control algal growth and reduce aquarium maintenance. Does not discolor water or cause foaming