I agree sand is never a good option. But playing the devils advocate, leopard geckos along with bearded dragons ate commonly mistaken to live in a sandy(desert like) biome, when really its a mixture of compacted dirt, clay and sand. Another thing to keep in mind is weather you feed them within the enclosure or a separate container. For me personally and just my opinion, whatever the substrate I always take my reptiles out and feed them in a separate container so there's no chance of accidental ingestion.