Exo Terra's Worm Dish allows reptiles to see their food, but the specially designed edge ring prevents the mealworms from escaping, while allowing them to remain visible to the terrarium inhabitants. Vitamin and mineral supplements can be easily added to the dish, and any excess powder can be reused. Mealworms need to be contained when they're placed inside the terrarium. If not, they will quickly 'escape' by digging their way into the substrate. The Exo Terra Worm Dish is constructed in two parts to facilitate cleaning. It is the ideal accessory to easily feed your reptile.