Marine sands Meridian - Seachem €39.90 Meridian Meridian is an aragonite substrate for all reef aquariums and marine aquariums. Its granulometria ( fairly uniform 0.25-0.50 mm) is ideal for reef inhabitants and its chemical composition will help to stabilize calcium and alkalinity avoiding a large decrease in pH. Formats: 3.5 kg and 9 kg Visualizza