Wow where did you get one only an inch?! anything live and wiggling can get him to feed. Mosquito larvae, black/blood worms, young feeders etc. The benefit of larvae or worms, if you can get him feeding at the surface, pellet training will be easier. If you want to use feeders, any live bearer will have small enough young and it would be easier to breed them yourself to avoid disease and give you more options for size. I would use worms or larvae personally