"There is something more powerful than each of us, a combination of our efforts, a Great Chain of industry that unites us. But it is only when we struggle in our own interest that the chain pulls society in the right direction..." - Andrew Ryan
Calci-O is a brand of drink produced and sold in Rapture. Since milk producing livestock was either not available or limited, this drink served as a milk substitute sold in Rapture. It contained "32% of your recommended daily dose of calcium" and was advertised to be the most effective milk substitute on the market. It was bottled to look like ordinary milk. It was a product of one of the businesses owned by United Seafloor™. Calci-O had various flavors of their products, including strawberry, which held the claim "Now your best source of calcium is even more delicious!"