line on my tang

i just got home from work and i saw a white line on my yellow tang please tell me what that is heres a pic

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I think he has just been scratched to be honest, maybe fighting with the other tang?

 

they dont fight and it looks much more that a scratch looks like a solid white

 

it just a off color patch all yellow tangs have them, but usually they only show up at night when the fish loses his color. don't worry about the line but the fact that hes showing it means hes stressed, worry about that.

 

That white line is called the lateral line I do believe- and its a sensory tool for every fish which aids the fish with learning about the parameters/conditions of the water around it. But yes, it generally does not show that pronounced during the day- typically only at night.

 

A lateral line picks up vibrations in the water that is used in feeding. Kind of like our ears.

 

I've seen quite a few yellow tangs with white patches and what not. Just normal colortion for some. It does seem to be more noticeable when they are stressed, so keep an eye on it.

 

so thats the lateral line, huh i wasn't sure if it was that or less noticeable line thats above that.


edit: i was looking it up i dont think the white patch is the lateral line i think its the line that right below the fin and follows the curve of the tang.

see where the sickness is that the lateral line the white line. it has head and lateral line erosion

 

Btw, when you are adding images to your post, don't use html, use the forum code, which is [ img ] [ /img ] but without space.

 

That's definitely not lateral line. Whoever posted the pic of the purple tang had it right. Lateral line is much thinner and higher up on the fish.

Looks like a stress thing to me. Just be conscious of tank size, compatibility with inhabitants (watch for bullying), water params, and make sure he's getting a healthy diet with marine algae on a clip.