The issue isn't the blue lighting for the tank, just that it is more difficult for us to ID things under blue light. For that, natural white light is best.
That said, your clownfish has an unidentified syndrome where the tissue under the skin turns darker. You can only see this change under the white bands though.
Here is a thread I started about this issue:
All, Over the past two years or so, I've come across dozens of cases on the fish disease forum here of an issue with clownfish that we have not been able to identify. I've never seen it on any clownfish I've had myself, but the issue seems most common on designer clowns, which I don't work...
www.reef2reef.com
Jay