White patch on purple tang?

[Benhuan]

Hi all,
I have had this purple tang for about 2 months now, he was eating really well mysis and nori everyday but recently im not sure what happened but he stopped eating mysis and eats little nori and now only eats pellets. He had ich ages ago but i did put him through copper before adding him so my DT is ich free. Today i noticed that he has these white patches on his side and that his fins are getting transparent. Parameters are all at nsw level and he is in a 5 ft 130 gallon tank. pls help id what it is. Flukes? Bacterial? (Photos are clearer on a phone)

 

[fishguy242]

bump

 

[Big G]

Might be both flukes and a bit of a bacterial infection from the flukes attaching to the skin of the tang.
Consider doing a freshwater dip to check for flukes. A dark colored container makes it much easier to see the small white-ish sesame seed sized bodies of the flukes after they fall off.

Freshwater Dip

Freshwater Dip What It Treats – Provides temporary relief for a wide range of diseases: 1) Marine Velvet Disease (Amyloodinium ocellatum) 2) Brooklynella hostilis 3) Uronema marinum 4) Flukes (Monogeneans) 5) Black Ich (Turbellarians) Can be used to confirm the presence of Flukes (see video...

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