Still not sure which tank you're talking about. If you mean the top tank (with lots of green/yellow) its a log from the reptile section of Petco. Its half buried in gravel, so its more like a tunnel, as there's an opening in the back by the filter as well. If you mean the bottom tank (white/brown/green) its a log from the aquarium section of Petco. Just about everything in my tanks are from Petco, plants, fish, frogs, everything. Occasionally I'll have something from Petsmart, but not often.