What we do is we take fish tank pebbles and put them in the tank instead of coconut crud, because really, if you buy big enough pebbles, they won't swallow them, they won't have dirt stuck to them all the time, and you don't get mold. Our whites are big enough that we take them out of the cage to feed most of the time, anyway. The frogs do end up getting a small pebble or two in their mouth, but you can just do out of tank feeds. and our little blue whites got rocks in his mouth once after tackling a cricket, and he spit them all out, so, gravel, in a big size is really nice.