Please tell me which company is best to buy real ocean stone and living sand from the ocean. My tank is two years old, I decided to change the sand, add about twenty pounds. And also change twenty pounds of living stone, maybe two or three. Anyone with experience, please advise. I have a RedSea Reefer 350.75 gallons. Will the living stone need to be treated for some time, or can it be immediately placed in the tank?