Green mandarin question

[AxiomOfthruth]

I picked up a green mandarin at my lfs about 4 days ago, after putting him in my tank he seemed fine for the first day but I noticed one of my diamond back gobies nipping at him on the second day. Since this happened he has spent all of his time in one corner of my tank up against a rock not moving. Will he adjust or am I going to have to pull my gobies out of the tank for a while to let him grow more comfortable?

 

[sporto0]

If it is just staying in the corner & not moving about, it will not survive, they spend the entire day (light) cruising for pods in & amongst the rocks, sometimes I don't see mine for a week because it is hidden in the rock work.