Chaetodon robustus also commonly referred as Three-banded butterflyfish is distributed in the Eastern Central Atlantic from Mauritania to the Gulf of Guinea, extends to Cape Verde.
Three-banded butterflyfishes live in their limited distribution area in depths up to 70 m usually in pairs. Actually, they are omnivorous and eat algae, worms, hydroids, crabs and shrimps, etc. . Chaetodon robustus is far less specialized, like many of his Genus.
So they are hardly suitable for a reef-tank, but a beautiful large fish-only tank, with many live rock is the ideal solution.
Butterflyfish are not recommended for reefs as they will pick at or eat a wide variety of corals, fan worms, and other invertebrates. Most Butterflyfish are known to pick at Aiptaisia, a parasitic anemone.