Hlle

[Paul B]

HLLE or Head and lateral line erosion or as we often call it "hole in the head disease" is just about the only aquarium malady that we can't yet cure or even know the cause.
I know what is not the cause because I have been experimenting on it for many years and I know all of the things that do not cause it.
Steven Pro hit it on the head when he said that it is caused by captivity
http://reefkeeping.com/issues/2005-06/sp/index.php

Wild fish supposedly are not prone to HLLE and I must say in 40 years of diving I have never seen it on a fish in the sea.
It is not caused by a lack of vitamin A (which I thought was one cause) it is not a lack of vitamin C (another thing I thought it was) or stray currents (another possability but doubtful), stress (this is blamed for everything)
A bacterial or viral infection has not been determined. But this malady affects a large majority of fish mostly tangs but many fish species can be affected. It is not fatal but sometimes the fish looks so bad you would wish it would die.
Also some tanks seem not to be at risk. I know that if I keep a hippo or yellow tang for a few years it starts to develop HLLE.
It could just be a small spot for years then it slowly spreads.
The hippo I have now is just missing a small patch of skin on his head, a positive precurser to the "disease" (if it is a disease)
I have been experimenting for three months by giving this fish large amounts of calcium, Vitamin A, C, and D.
The spot is still there but the fish is very noticably brighter. His blue is very blue and the black is very black. But the experiment is a failure because I know this fish will still get HLLE.
I have had dozens of Hippo's and they usually live over ten years but if I remember, they all got HLLE eventually.
I am going to keep giving those vitamins just because of the improved color but I still need to know before I croak what in captivity causes this ugly disease.
Paul

 

[Billybeau1]

This isn't the first time I've heard about vitamins fighting HLLE as well as fin regeneration.

I know one thing it is not. Stray Voltage. This is one of the biggest misnomers in the hobby.

I once brought a blue angel back to the lfs because it was outgrowing my tank. It had a mild case of HLLE. The owner insisted I had stray voltage in my tank.

I do not and I think I know how to measure for it. :lol:

It seems to only affect bigger fish so the captivity theory is certainly believable. But like you said, wha is it about captivity that causes this

 

[Paul B]

I am also an electrician (40 years) and I also doubt it is stray voltage. I have a ground probe in my tank for the last 20 years and I diden't have one for the first 20 years. No difference in the rate of HLLE.
It is a very prevelent affliction as almost all the yellow tangs in captivity for a while has it to some degree. Yellow tangs in the sea just look so much better and much yellower.
Hippo tangs in the sea are one of the best looking, most colorful fish but in a tank for a while and they look so much different.
This "disease" or whatever it is probably affects all fish to some degree but it may be only in tangs and a few others where it is noticable. If we could find the cause I am sure it will benefit the health of all captive fish.

 

[Paul B]

Does anyone here have a yellow tang ot hippo tang for five or ten years that does not have any HLLE? If so I would be interested. It's a start

 

[Jens Kallmeyer]

HI

I got a Red Sea Tang (Z. xanthurum) from my LFS some time back. It was "rescued" from a customer's tank. The fish was basically just a piece of meat with gills, basically no fins and about 50% of the sides were eroded.
The one good thing about the fish was that it was still reasonably active and eating. All I did was keep the fish in a tank with very docile mates and quite a few algae (hairy, Caulerpa, different red algae, etc.), feed it a very diverse diet and using different vitamin and amino acid additives. Now after about 7 months the fish has completely regrown its fins and the sides are now healing again, all that is left at the moment are two black spots behind the head but those are also getting smaller.
In my opinion the main (perhaps not the only) factor for HLLE is malnutrition. I wouldn't want to nail it down to a single Vitamin, but I am pretty sure that in many cases we simply do not provide them with all the essential nutrients that the fishes need.
Peter Schmiedel's yellow tangs must be way over 5 years old, he got them several years back and at that time they were already pretty old. His tangs do not even have a trace of HLLE, they rather have problems with cholesterol.... See here in the middle of the page

Jens

 

[Paul B]

That yellow tang looks like my Hippo and he does not have a trace of HLLE. It still could be something else in his tanks that is beneficial or something that is missing. I don't think it is just food but I could be wrong.
I may ask him.
Paul

 

[Jens Kallmeyer]

HI Paul

I am still waiting to see a fat tang with HLLE. So far, all the fishes I've seen with HLLE were rather skinny.

Jens

 

[Paul B]

Jens, if I get a chance I will take a picture

 

[dynamixone]

i have a juvi imperator that is just finishing up in qt from ich or velvet.

it is showing signs of hlle. its got to be from the qt tank conditions. I am trying to get him back into the dt asap as hopefully it will reverse it.