Help identifying brown spots on tang

[artieg]

I added Atlantic blue tang to aquarium one month ago (did not QT, never make that mistake again). Shortly thereafter it developed lympho (100% certain, looked like blotches of mayonnaise on end of fins). It was eating like a champ and the lympho was starting to clear up when this morning a whole new outbreak of brown spots showed up. See photos. Did his diminished immune system leave him vulnerable? Have a QT set up and ready if I need to pull him out, obviously hindsight = 20/20.

Brook or velvet? Definitely brown spots, so not ich. Weird, the tang is the healthiest acting fish I have ever seen, zooms all over, eats everything, playful, etc.

Details: 180g FOWLR tank is 3 months old. Earliest inhabitants are porcupine puffer and midnight angel, both healthy and not showing any signs of the crud that the tang has. Water parameters: no ammonia or nitrite, tiny sliver of nitrate.

 

[snorvich]

Black Spot Disease, Tang Disease or Black Ich is actually caused by an infestation of tiny Genus Paravortex member turbellarian flatworms. Treat with Prazipro twice a week apart.

 

[artieg]

Quick question: Given I have a fish only tank and no worm type inverts, is it ok (not ideal, but ok) to treat the entire DT with Prazipro (obviously, remove carbon)? Or would you separate the tang, treat it in HT, and observe the others in the DT?

Thanks!

 

[artieg]

Last update: the spots only show up first thing in the morning. By midday, with lights on, they disappear. Back next morning. Just a weird tang coloring thing? Part of the expected coloration of flatworm infestation?

Thanks!

 

[Naraku]

I personally think it is coral sting marks.

Its still better to be safe. Have you treated as suggested by snorvich yet?


Edit: nevermind, its a fowlr, no corals. It could be a skin reaction from the lympho though.