Very tough to get to eat and very shy. I had one a few years ago. Got it same day it arrived at the LFS in perfect shape. Took maybe three weeks before he ate anything (you name it I tried it). Eventually it started eating simply chopped raw shrimp after refusing it countless times. Even so it was always a challenge to get it to feed. It did not eat every day. I managed about 6 months, then it just died. They are beautiful but without doubt a very difficult fish to get to thrive.
Someone might have better luck keeping it alone in say a 55 or so, but purely a guess.