Dimart Aquarium Ceramics Tank Dental Mouth Shape Ornamental Shrimps Shelter Tubes Breeding Hiding Spots(Gray + White, S) High quality, made of ceramics, very durable and practical. Water purification function, adsorb microorganisms. No pollution, non-toxic, no harm to fishes and shrimps. Create a natural ecological environment, very comfortable for fishes and shrimps. Great shelter for shrimps, small fishes, baby fishes. Also a great decoration for aquarium fish tank. It can act as a breeding ground for fishes and shrimps, also it will be a best playground for shrimps and fishes!