Wow, if this is the same yellow tang that you have multiple posts on over the last several months, it is deteriorating quickly. A couple months ago, the fins looked much better and it looked like HLLE
was the issue. in those prior posts, you have been given suggestions when it appeared to just be HLLE
. Are you following them?
I also notice in other posts that people have asked how big the tank is and an answer was never given. Im going to assume by the picture, its at least half the size it should be.
Not to be mean, but this is another example of a stressed tang in a tank that is too small. Stress will bring on several health issues with fish. IMO
, the answer is to get it into a proper sized tank, maintain pristine water conditions and make sure its eating a proper diet, with lots of seaweed/nori. I'd supplement with vitamins as well. Keeping it in a small tank is leading to a slow death.