Dr. Moss Stone Ceramic Aquarium Ornament M - CICHLID Rock Cave decor bonsai hide Spawning 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. Use small thread to bundle the moss on the product constitute a nature living environment. Measures approximately: 4.4" X 2.9"X2.3" (11.4 X7.5X 6 cm) (L x W x H )