I am setting up a reef tank and i am trying to findout what kind of sand you use. I have found this guy who sells aragonite sand and his company is zoosands but i want to know if this is good? He has different sizes what size do you recomend he has 1/12", 1/15" and 1/20" wich one will be better? Please help i dont want to spend a whole lot since i will need a lot of it. He quoted me at .45c per pound.