I have a sulcata tortoise, and I had to buy calcium and vitamin supplements from Petsmart. I don't know of any food in my area that already has both. I just put both the calcium powder and the vitamin powder in a couple salt shakers (unused of course). Then, I sprinkle this lightly on his food. I know that's probably not the answer you were looking for, but that's all I know to tell you. Here's the link for the supplements that I purchased (and they last a long time! I've had my little guy for 1.5 years, and I still have most of it left):Vitamins:
http://www.petsmart.com/global/produ...66694&Ne=288It is important to provide your slider with Calcium also, because he is mostly bone. If not, he could develop "soft shell syndrome."