1. The aquarium decor cave: Shrimp Shelter Tube provides shelter and hiding spots for fish, also can be used as spawning sites. The Shrimp Shelter Tube is suitable for small bream, shrimp, cichlids or other small fish when they need a rest and having fun. 2. Its smooth edges, won't scratch your fishes., which create a natural and living environment for fish. And the Shrimp Shelter Tube is made of ceramic, possess filtration function in your fish tank. It not only suitable for fresh but also salt water.