No, in most of my tanks they are out all the time. But that may depend of the fish in the tanks. Most of my Amano-containing tank are heavily planted with fairly wimpy schooling fish which never pay any attention to the Amanos.
How long have you had it? It might be molting. 1 out of my 4 amanos is usually hiding away molting at any given time. Otherwise they are out happily shredding my driftwood.