Mark on tangs

[JMorris271]

Hi RC
Last week I noted that both of my tangs have a mark on each side of their body.
Could these be an abrasion of some sort from cutting in to the rock too fast for example or does it look like battle marks? These marks are all located in the same place on both fish.
Any ideas on what this is?
Thanks

 

[Squidmotron]

That's just an ordinary part of the fish.

 

[Jeff4777]

Those are normal markings on Tangs

 

[kmbyrnes]

They also become more noticeable in dim light. Nothing to worry about.

 

[mcgyvr]

The lateral line

 

[scooter31707]

I was told if it turns white, that's a sign the fish stressed out.

 

[lockdown52]

Yep. Those are normal markings.

 

[JMorris271]

Thanks everyone.

 

[EdgeN]

Stress marks IMO.. Discus used to exhibit these too. (the lines vertical)

 

[ssick92]

Not necessarily stress markings, but yes most fish have different colors that they can turn when they feel stressed, hungry, etc.

 

[reef_aholic]

my yellow tang shows the lateral line like that when i have the lights off for some maint or acclimation of some sorts.

 

[JMorris271]

I see more redness or closing of fins associated with stress.

 

[SeaCucumberFan]

I see more redness or closing of fins associated with stress.

I'm pretty sure closing of fins isn't stress but not sure about redness. Is it a fish only tank or did you put in fish first?