I've got a yellow clown goby in a 46g. No issues with him hiding - it's out and about all the time. Normally perches on a platygyra, but his #2 favorite spot is camping out on my acans. At night, he hides in the branches of a Duncan and thinks he's hidden! Really nice fish with lots of personality. I've never had him nip at any corals, but I have no acros. He doesn't bother the seriatopora or the stylophora, or any of the LPS.