We’ve had this convict tang for a couple years now and it looks like he’s developing HLLE. The divots around his face have been there for a while, but I think the ones going along the side of his body are relatively new. He eats well as you can see he’s very fat. The water quality is good as far as I can tell. Our nitrates are a little high, but nothing out of control. I’m not really sure what’s causing this or how to address it. Any thoughts?