Yellow tang white spot.

[Jeisold]

My yellow tang has presented with a single white spot, apologies for the low quality photos was hard to get. The spot I'm talking about is the one mid upper body. To the naked eye it does appear 3 dimensional sticking out from the fish. There seems to be a darkening (more orange than yellow)of the skin around the site. At least to me it does not seem like ich, as it's protruding visibly and there's only this one across this fish and no others in the tank have any. The fish is eating, however seems reduced, not nearly the pig he usually is.
I have performed a FW dip and is now in a bath of ruby reef rally, as this is what I have on hand.
Any ideas on what this is and how to proceed?

Fyi..The white circle in the one photo is not on the fish, the spot right above it is the one im going after

 

[vetteguy53081]

My yellow tang has presented with a single white spot, apologies for the low quality photos was hard to get. The spot I'm talking about is the one mid upper body. To the naked eye it does appear 3 dimensional sticking out from the fish. There seems to be a darkening (more orange than yellow)of the skin around the site. At least to me it does not seem like ich, as it's protruding visibly and there's only this one across this fish and no others in the tank have any. The fish is eating, however seems reduced, not nearly the pig he usually is.
I have performed a FW dip and is now in a bath of ruby reef rally, as this is what I have on hand.
Any ideas on what this is and how to proceed?

Fyi..The white circle in the one photo is not on the fish, the spot right above it is the one im going after

I dont see this as disease as i do puncture would or small bite marks. What other fish are in the tank with it?
If you have an urchin or anemone, they would be my suspects.
Keep an eye on fish for healing and not becoming red or sore. If so, treatment in a separate tank would be Seachem neoplex

 

[Jay Hemdal]

Also, the tang is a bit thin. You should bulk it up by more frequent feedings of meaty foods - pellets, diced mysids for example. 3 or 4 small feedings a day, at least until it bulks up a bit.

 

[Jeisold]

Thank you all. The spot did disappear from the dip, Unfortunately my yellow passed overnight. This was rapid, he wasn't as thin or as pale. Obviously my fault as it's my pet, I can't think. Raised him for almost 2 years. Thanks