Are you acclimating it to your lights? It is slightly bleached, and those lights could be a bit much for it right away. I would suggest putting 3 layers of window screening (( supported by egg crate )) b/t the lights and the tank.
M. doreensis are sandbed dwelling anemones, how deep is your sandbed?
What are your current water parameters -- with numbers please.
How much flow do you have? Are your powerheads covered?