I don't know whether you know this, but that doesn't mean they have been eaten, it means they burrowed in your substrate. I barely ever see my kuhli loaches and I have 5 in a 17 gal. Try looking at night, you may only see heads poking out, but they are there.i put some khulis in my 180L with shrimp about two months back. havent seen any of either of them since lol!