I learned something quite by accident. I took in an aggressive, deformed box turtle and put him into a temp enclosure on my carport. I didn't have time to set the enclosure up properly, just a light and substrate. When it came time to feed him, I didn't have ready access to a feeding tile, so I grabbed a cuttlebone and using it soft-side up, placed the turtle's food on the cuttlebone. He ate the food that day and the next, then by the third day, I guess he had gotten used to the smell of the cuttlebone, and he even ate a bit of it along with the food.