Purple tang huge white spot

[ACIAMPA]

Please help I have had this purple tang over a year and just today a huge white spot is spreading from his underbelly. It almost looks like cut off circulation. He’s always been super healthy. Ive had no major parameter swings, I saw him just an hour ago and looked fine. I do have a long spine urchin which I know is venomous. I’m thinking maybe he got poked. If so, what’s the prognosis is he gonna die?!?!

 

[ACIAMPA]

Note: despite the spot he seems to be swimming and grazing just fine however I’ve only been watching him for 10 minutes

 

[Jay Hemdal Verified Community Expert]

Please help I have had this purple tang over a year and just today a huge white spot is spreading from his underbelly. It almost looks like cut off circulation. He’s always been super healthy. Ive had no major parameter swings, I saw him just an hour ago and looked fine. I do have a long spine urchin which I know is venomous. I’m thinking maybe he got poked. If so, what’s the prognosis is he gonna die?!?!

I've never seen urchins cause blanching like that, and if it was the urchin, you should be able to see a point where the spine entered.

Since it is mostly on the left side of the fish, and it started up quickly, I think you can rule out disease - the spot would be more symmetrical or random, and it would not have grown that fast.

I wonder if it ran into a stinging coral?

Jay

 

[ACIAMPA]

As far as stinging goes I have a couple Euphylia and a bubble tip. I would guess the bubble tip but I’ve seen my tangs bump into them with no problems in the past. also have a space invader and galaxea but they’re still small.

 

[vetteguy53081]

This looks very similar to a spot my naso had when I acquired it. The fellow was feeding the fish staple- not a true diet and his water was not the best as he stated he had no time for water changes. Less than a month later, with water quality in an improved environment and good diet- its colors are restored.
NOT saying its water quality or diet in your case but I would confirm water conditions or change in water whether it be overdue maintenance or addition of component such as skimmer or even carbon/resins.
What test kits are you using?
RO cartridges expired?
What foods are you feeding it? (belly appears slightly pinched)

 

[ACIAMPA]

Gave it some time and the spot started getting smaller now it’s barely there. I think it may have just been like a skin irritation. it’s behavior didn’t seem affected in any way. Thanks guys
To answer your questions:
- Hanna nitrate phosphate, Neptune trident
- I use an auto feeder twice a day plus frozen food at night, nori every other day
- rodi filters look good 0tds I run a 7 stage