Wio Cholla Drift/Cactus Wood is a natural, lightweight wood made from the dried skeleton of the cholla cactus, supplied as 5 pieces per bag. Its hollow, branching structure makes it a popular choice for shrimp tanks, giving shrimp plenty of nooks to hide, graze, and moult in safely.
The textured surface of the branches naturally develops biofilm, which shrimp and other bottom dwellers will graze on as a steady food source. The wood is also soft enough that rasping fish, such as plecos, can supplement their diet by grazing on it, and it's a great base for tying on mosses to create a more natural, aquascaped look.
Cholla wood tends to float to begin with, so boiling the branches before adding them to the tank helps them waterlog more quickly and sink.