Uhhh...Could you narrow it down a bit? People use just about any kind of sand in their tanks. Some use sandblasting sand, some use beach sand, some use river sand, some use pool filter sand, some use propogating sand, some use coarse sand, some use find sand, some use light colored sand, some use dark colored sand. Some use angular sand, some use rounded sand, some use lots of sand, some use a little sand, some use pile the sand up towards the back, some have it level...