Did you just get it?
It actually doesn't look that badly bleached, though it could get better. There's still a slight brown tint in the tentacles. The lighting shouldn't be a problem. Feed it meaty foods like mysis, krill, silversides, etc. to help it recover.
It does appear to have a low population of zooxanthellae, however overall physical health doesn't look too bad.
As ViPeR suggests give it some meaty foods couple times per week. keep the water clean so the light can penitrate well.
Thomas