Give it some time. My tomini tang was very skittish at first, often scraping his sides in a mad dash to hide in the caves. I made sure to get a lot of face-time with him, feeding up 6 - 7 times a day in small amounts. He eventually got used to me and is often hand-fed. Greets me like an excited puppy now. He still is nervous around other people, so it appears he can discern different faces.