Rubberlipped pleco doesn't come out at night?

My rubberlipped pleco spends most of his time during the day in his log, occasionally he comes out and cleans around his log, but at night I peek in and he's in the same spot every time I see him, only sometimes he cleans the glass at night
he's most active in the day
why?

 

Some pleco's like to hang out during the day, where some like to come out more at night. I found that after I put my tank lights on a timer, my Clown gets more active the closer it gets to lights-out, and he's out pretty much all night. I think he likes the more solid day-night cycle.

 

hmmm, my rubberlip isn't the most social fish.

perhaps it's pinned down by the shark. Sharks are very territorial and maybe the pleco won't leave because it's protecting it's spot.

 

Oh, I didn't even see that! Rainbow sharks can be little terrors. You may not see it, but it could very well be happening. Do you have other caves and such in the tank, so they don't have to share?

 

Ya no one messes with his log the shark doesn't get close