Fallen Fortress (Dark Blue 3618) custom formicaria I would recommend a medium

I would recommend a medium sized nest for them because the chambers and tunnels for the Pioneer are larger on average than  some of our other nests

Premium Woodland Decor (+5)

Pogonomyrmex occidentalis are a medium-sized ant species so we will make chambers sized for them unless you state otherwise in your comments

Stopper for connection port (1/2" and 3/8" port for connection)

***If you are ordering the product on this page you will receive the formicarium shown in the photos along with any options you choose

Fallen Fortress (Dark Blue 3618) custom formicaria I would recommend a medium***Ordering the product on this page? You will receive the exact formicarium in the photos accompanying this product page. This formicarium has already been made and can be modified only with the options for glass type and removable vent lid.*** Features: Medium Large Species Chambers Decor (Per Product Photo) Large Water Tower (15 ml capacity) Magnetically Removable Glass Type III Material 4x4x4 Foraging Area 4x4x2 Nest Block The Fallen Fortress is a