JBL Sansibar White is a white natural substrate for any aquarium. JBL Sansibar White is a fine rounded quartz sand, just like the one found in the native waters of the aquarium fish. It is gentle on the sensitive barbels of bottom-feeding fish such as cory catfish and loaches. The fine grain size and dense layering prevent sludge and other debris from seeping in, thereby preventing decay processes which could hamper plant growth. JBL Sansibar White does not release hardness-producing substances or undesired silicates into the aquarium water. Grain size: 0.1 - 0.4 mm.