Cholla wood is from the Cholla Cactus. It is a very popular wood for any aquarium that houses shrimp, due to its abundance of holes and the large hollow tunnel through the center. The Cholla wood also grows biofilm, which is a shrimp favourite. 

Care info:

• Like any wood that is placed into an aquarium, Cholla may need to be held down with something, or half buried into the substrate until it is waterlogged (completely saturated in water and does not float back up to the surface).