sailfin with HHLE
 

I have a red sea sailfin ~ 8" that has developed HHLE on one side of her head.

She gets a sheet of nori a day (shared with1 other tang), frozen food supplemented with vit C, and occasionally some pellets.

water params
-sg=1025
-nitrite =2
-ammonia=0
-temp = 26C/79F
-ph = 7.8 (low, but it is steady at this since I set the tank up 2 years ago)

no stray voltage

Any other ideas on what could be causing this? It seems to be getting worse instead of better. She is queen of the tank, so I dont believe it is stress.

do you run carbon? If so you should remove it as I have read that some study show that carbon can cause HLLE in tangs.

what type of frozen food do you give? I suggest PE mysis if you can find it.

I have one with the same issue. It had absolutely no top fin when I got it. Now it is showing some good recovery. I have been feed with a mix of formula one pellet and formula two pellets, PE Mysis.

What types of nori are you feeding it?

I don't know if it was just a myth, but someone told me once that brown algae (Phaeophyceae genera) contains a bunch of chemicals that help ward off HLLE, and that sheets of green nori might not be nutritious or diverse enough on their own. I have bought every colour and species of algae sheets that I can find (species from the Rhodophyta, Chlorophyta, and Phaeophyta families) and feed them on a rotating basis. Just make sure that it's actually different algae species, and not cheap food coloured ones.