Hlle?

[conjuay]

I don't believe this is HLLE because it looks more like a single puncture rather than 'erosion'. The fish has had it a considerable time, without it healing or becoming any worse.
I think he was slapped by one of the other tangs in residence.
Any thoughts on curing it?

 

[BBraker]

No - that looks like HLLE. In rare cases, it can be unilateral. The fact that it has been there a "considerable time" is key to this diagnosis.

 

[conjuay]

Thanks, I will have to try and research this (HLLE) more carefully. I've read briefly about it over the years, but now I've got to dig much deeper.

 

[ThRoewer]

Do you use activated carbon? Possibly the cheap lignite (coal-based) variety or the even cheaper stuff made from coconut?
That has been proven to cause HLLE:
Activated Carbon: HLLE Smoking Gun Found
Activated carbon affirmed as causative agent for HLLE disease

 

[krullshards]

Thanks for those links ThRoewer, everything I had read before was a lot of conjecture.

 

[ThRoewer]

Activated carbon is only one of the possible causes, though the easiest to eliminate.

Insufficient nutrition or other pollutants are other possible causes.