Head and Lateral Line Erosion (HLLE)

[brwaldbaum]

It depends. The carbon free tank has to have a total history of no carbon use. Many people feel there are also other causes for HLLE. Trouble is, none of those causes have been proven. If at some point, one or more of them are studied, then they would also have to be mitigated. I've tested a few of the alternative ideas - I think I can rule out stray voltage as well as dietary enhancements (as a cure). I'm still not able to rule out heavy metal toxicity and truly deficient diets.

Jay

Although I only have access to the abstract, Stamper noted healing of lesions once the carbon use was discontinued. He used coconut shell carbon, which I think is a hard, relatively dust-free carbon. Do you attribute the healing he observed to the type of carbon he used?

 

[Jay Hemdal Verified Community Expert]

Although I only have access to the abstract, Stamper noted healing of lesions once the carbon use was discontinued. He used coconut shell carbon, which I think is a hard, relatively dust-free carbon. Do you attribute the healing he observed to the type of carbon he used?

We didn’t see healing in our fish until after the study was concluded, so that data couldn’t be used. Only the fish with minor lesions healed. The severe ones were in a bad way and were euthanized.
Jay

 

[brwaldbaum]

We didn’t see healing in our fish until after the study was concluded, so that data couldn’t be used. Only the fish with minor lesions healed. The severe ones were in a bad way and were euthanized.
Jay

Are they using Regranex here?

 

[Jay Hemdal Verified Community Expert]

Are they using Regranex here?

I think so. I’ve never used it, and haven’t heard of any aquariums using it recently. One of my staff was the curator at Greensboro, I can ask him if he knows about that case, but it was probably after his time there.
Jay

 

[brwaldbaum]

We didn’t see healing in our fish until after the study was concluded, so that data couldn’t be used. Only the fish with minor lesions healed. The severe ones were in a bad way and were euthanized.
Jay

Why aren't fish with (severe) HLLE constantly bumping into stuff? I thought fish need their lateral line for navigation.

Also, are fish with HLLE more prone to bacterial infections?

 

[Jay Hemdal Verified Community Expert]

Why aren't fish with (severe) HLLE constantly bumping into stuff? I thought fish need their lateral line for navigation.

Also, are fish with HLLE more prone to bacterial infections?

Fish use their lateral lines to feel pressure waves from predators, they use eyesight to navigate and see food items.
Yes - in really severe cases of HLLE, histopathology showed concurrent bacterial infections. Under good conditions, fish seem to be able to manage moderate HLLE without the lesions becoming infected. I’ve had affected sailfin tangs live for over a decade with it.
Jay

 

[brwaldbaum]

We didn’t see healing in our fish until after the study was concluded, so that data couldn’t be used. Only the fish with minor lesions healed. The severe ones were in a bad way and were euthanized.
Jay

Was there substrate in your experimental tanks?

Was the fishes' feces examined for the presence of carbon fines?

 

[Jay Hemdal Verified Community Expert]

Was there substrate in your experimental tanks?

Was the fishes' feces examined for the presence of carbon fines?

Our study tanks were bare bottom with live rock for passive biofiltration. The presumption was that the carbon fines were an external irritant, so we didn't consider that they would eat the fines and cause HLLE that way, so we didn't look at the feces.

The two competing studies (ours and Disney's) both concluded that carbon causes HLLE in surgeonfish, but neither of us were able to prove the secondary hypothesis of "why". Disney thinks it was due to an interaction of heavy metals and carbon. We think it is due to the physical presence of carbon fines.

Some months after our study, a researcher told me that he had isolated carbon fines from a surgeonfish with HLLE, using an electron microscope. I cannot confirm that though. I think the Disney study missed the mark by implicating heavy metals - their idea is that heavy metals bind with organic materials, reducing their toxicity, but by adding carbon, that removes the organics, freeing up the heavy metals, that in ionic form, are more toxic. The trouble I have with that is that our experimental tanks were freshly set up and did not have high organics, or any extra heavy metals. Besides, my understanding is that carbon removes the bound organic/metal compounds at the same time, and doesn't split the bond and just remove the organics.


Jay

 

[brwaldbaum]

Our study tanks were bare bottom with live rock for passive biofiltration. The presumption was that the carbon fines were an external irritant, so we didn't consider that they would eat the fines and cause HLLE that way, so we didn't look at the feces.

The two competing studies (ours and Disney's) both concluded that carbon causes HLLE in surgeonfish, but neither of us were able to prove the secondary hypothesis of "why". Disney thinks it was due to an interaction of heavy metals and carbon. We think it is due to the physical presence of carbon fines.

Some months after our study, a researcher told me that he had isolated carbon fines from a surgeonfish with HLLE, using an electron microscope. I cannot confirm that though. I think the Disney study missed the mark by implicating heavy metals - their idea is that heavy metals bind with organic materials, reducing their toxicity, but by adding carbon, that removes the organics, freeing up the heavy metals, that in ionic form, are more toxic. The trouble I have with that is that our experimental tanks were freshly set up and did not have high organics, or any extra heavy metals. Besides, my understanding is that carbon removes the bound organic/metal compounds at the same time, and doesn't split the bond and just remove the organics.


Jay

Did he mention the approximate size of the particles? I ran fresh, non-dusty carbon in series with a 20 micron cartridge filter, but the tangs developed HLLE within two weeks of adding the carbon.

 

[Jay Hemdal Verified Community Expert]

Did he mention the approximate size of the particles? I ran fresh, non-dusty carbon in series with a 20 micron cartridge filter, but the tangs developed HLLE within two weeks of adding the carbon.

VERY tiny. We sent samples out for histopathology and they didn't see any through regular microscopy.

Just off the cuff, we use carbon filters on our RO system, but the membrane is going to stop all fines. We don't use raw carbon on any marine fish systems. I think 20 micron is too large though.

Jay

 

[Tft12]

VERY tiny. We sent samples out for histopathology and they didn't see any through regular microscopy.

Just off the cuff, we use carbon filters on our RO system, but the membrane is going to stop all fines. We don't use raw carbon on any marine fish systems. I think 20 micron is too large though.

Jay

@Jay Hemdal thank you very much for this article and this thread.

I started using ROX 0.8 about 4 months ago and two of my tangs have developed extremely slight HLLE. I use about 2 cups of GAC at a time and rinse it with 10 gallons through the reactor into a bucket before each use. I’m going to either put a 1 micron sediment filter inline following the GAC or stop using GAC entirely.

I read in your last post that you don’t use GAC on any marine fish systems. Are you referring to all systems that have marine fish? Are you using something as a substitute for GAC? Do you believe GAC is doing anything important in a reef tank that would lead to trouble if GAC is omitted long term?

 

[Paul B]

Hey Jay. Look at the fish my "friend" gave me yesterday. It's in my tank, great isn't it? :rolleyes:

 

[Jay Hemdal Verified Community Expert]

@Jay Hemdal thank you very much for this article and this thread.

I started using ROX 0.8 about 4 months ago and two of my tangs have developed extremely slight HLLE. I use about 2 cups of GAC at a time and rinse it with 10 gallons through the reactor into a bucket before each use. I’m going to either put a 1 micron sediment filter inline following the GAC or stop using GAC entirely.

I read in your last post that you don’t use GAC on any marine fish systems. Are you referring to all systems that have marine fish? Are you using something as a substitute for GAC? Do you believe GAC is doing anything important in a reef tank that would lead to trouble if GAC is omitted long term?

Correct, we only use GAC on a limited basis in some coral systems, or as a pre filter for city water. Our fish only systems are managed through water changes and buffer support.
Jay

 

[MnFish1]

Correct, we only use GAC on a limited basis in some coral systems, or as a pre filter for city water. Our fish only systems are managed through water changes and buffer support.
Jay

OH GOSH - that was the kiss of death (water changes LOL)

 

[\m/reefsnmetal\m/]

Ok I'm confused. I have 2 separate systems the younger of which is 1 1/2- 2 years old. Each system has a sailfin tang in it and each system runs carbon. I used to use red sea but the media bag opened and some of the carbon got pumped into the DT in one system. Neither of my tangs have had issues. Have I just been lucky? Should I quit running carbon to be safe or just keep doing what I'm doing?

 

[Jay Hemdal Verified Community Expert]

Ok I'm confused. I have 2 separate systems the younger of which is 1 1/2- 2 years old. Each system has a sailfin tang in it and each system runs carbon. I used to use red sea but the media bag opened and some of the carbon got pumped into the DT in one system. Neither of my tangs have had issues. Have I just been lucky? Should I quit running carbon to be safe or just keep doing what I'm doing?

Tough to say! Some people run carbon long term with no issues with their tangs. Most of them use pelleted carbon, rinse it well, and/or use good mechanical filtration on their tanks. Even protein skimmers help with carbon dust removal. Soft, dusty carbon, or carbon that has been ground up by mechanical action (like in a reactor) seem to cause the most problems. If you are not seeing issues with your sailfins (a species known to have issues with carbon induced HLLE) you are doing something right, so I don't see any real reason to change what you are doing.

Jay

 

[MnFish1]

Tough to say! Some people run carbon long term with no issues with their tangs. Most of them use pelleted carbon, rinse it well, and/or use good mechanical filtration on their tanks. Even protein skimmers help with carbon dust removal. Soft, dusty carbon, or carbon that has been ground up by mechanical action (like in a reactor) seem to cause the most problems. If you are not seeing issues with your sailfins (a species known to have issues with carbon induced HLLE) you are doing something right, so I don't see any real reason to change what you are doing.

Jay

I have had no issues - but It could be an 'amount difference' - for example - I drop some purigen into my sump - thats not like running a huge carbon reactor. Right? Not sure its totally clear

 

[\m/reefsnmetal\m/]

use pelleted carbon, rinse it well, and/or use good mechanical filtration on their tanks. Even protein skimmers help with carbon dust removal.

Jay

This is what I'm doing with both systems. Thanks for the reassurance, just trying to do what's best for both tanks but not at the expense of my fish.

 

[brwaldbaum]

Hey Jay. Look at the fish my "friend" gave me yesterday. It's in my tank, great isn't it? :rolleyes:

"fish"

 

[chadfish]

I just started carbon after the addition of my first tang - a Tomini. I am using large diameter pelletized carbon in a reactor with no fluidized motion or grinding. The reactor output is fed into a 5 micron filter sock. I am monitoring the fish each day and report any HLLE within 30 days. Not scientific, but maybe a good anecdote.