What is this?

[rvlcf]

My Naso Tang developed this mark. Wasn’t there yesterday.
Thanks in advance for the help!

 

[Big G]

Looks like rub marks. Keep an eye on it in case of infection.

 

[MamaLovesHerReefTank]

#reefsquad

 

[redfishbluefish]

@4FordFamily , you know your tangs.

 

[4FordFamily]

That looks like a sting to me, especially with how fast it reached that level. If it starts to turn reddish and grow quickly, the fish will need to be removed and treated with antibiotics but at this point I’d feed it varied offerings, lots of nori, keep the water as clean as possible, etc.

 

[Big G]

Anything new "wet" introduced into the tank within the last 30 days or so?

 

[Maritimer]

I tend to agree with @4FordFamily here - looks like hypermelanization from a sting - anemone, hammer or frogspawn coral or the like.

Generally will heal up on its own, but watch for bacteria to develop.

~Bruce

 

[MSB123]

+1 on the sting, happened to my blue tang recentelly, its slowy healing up

 

[rvlcf]

Almost fully healed. Happy ending. Thank you all for your input!

 

[rvlcf]

Full tank shot.