I have a pair of O. Clowns in my smaller tank...male "sleeps " on top of my mag-float and the female on the underside. In my larger tank I have a pair of P. Clowns...the female will actually lay completely down in the soft sand at night to sleep while my male sleeps in the top right corner. During the day however they run derby up one side and down the other, my male loves to make ripples on the surface...my favorites to watch lol!Mine seem to never leave the top corner of the tank, coming up on 8 months.
For over 2 years my clown stayed in the top corner of my tank but yesterday my 3 year daughters found "Nemo" on the floor. I think I was more upset than they were.