STONE Ceramic Aquarium Ornament - CICHLID Rock Cave decor bonsai hide Spawning Eco-Friendly Ceramic Replicas are great homes for live bearing tropical fish, most notably South American and African cichlids. Spacious interiors encourage exploration while providing secure breeding niches and a defensible, stress-reducing refuge. Ceramic stones provide a lightweight alternative to real stone in your aquarium. The hollow caves provides shelter, hiding spots, and spawning sites for your cichlids. Since they are hollow they do not displace or reduce the amount of water in your aquarium.