Jack Dempsey is hiding?

I have a medium sized Dempsey w/ one female convict and a sucker fish (plec) in an hexagonal 45 gallon tank, and he used to come out and watch me, but ever since i added the convict and sucker he just hides in an ornament all the time. I don't think he is sick, but how could I get him out? He's been like this for weeks.