yellow tang coloration. semi-urgent.

[GrotesqueHybrid]

i recently purchased a yellow tang. its been doing fine and eating all that i feed it. (sushi sheets, romaine lettuce, tank algae, spirulina enchanced brine shimrp and an omnivorus mix for yellow tangs) its been fine all day but when i went to check up on it just now i noticed a opaque brown spot on its side and a white stripe on its middle (not its blade on the tail, right smack dab in the middle of the body) what in god's name is this!? i'm usine marine-glo lighting and all my water chemicals are fine. please answer with any advice.

i was recently at about.com forum and they told me it was because of the lights turning off (lights on a timer). this could be it because my clowns act also act very peculiar when the lights go out but i want to make sure. thank you.

 

[reefrunner69]

It sounds like a stress coloration to me, most fis will pale when the lights go out. I have seen many yellow tangs exhibit the white line you describe and a few exhibit the brownish patch, without other symptoms I would not consider it a sign of a problem.