I assume you're referring to pomacea bridgesiis as I haven't seen any other ivory apple snail species. Mine eat Wardley's shrimp pellets, tetramin bottomfeeder tabs, frozen bloodworms, frozen brineshrimp -- they'll eat any sinking fish or reptile food, ones with higher protein and fat are more readily accepted and better for them. Like all applesnails they have separate sexes. They begin mating around quarter size and can start laying eggs soon after.
Amanda