Why do skinny fish die?

[Paul B]

OK I have a theory and only a theory. As long as I have been keeping fish I am drawn to odd shaped fish like copperbands and long nose butterflies but I could never keep them as long as most other fish and looking back there were two causes for their deaths. One was jumping out. For some reason those types of fish like to jump. I lost about half of them from that. The rest of them died from something else. Last year I lost a copperband that got a bump and then a sore on it's side just before dying. I remembered that a lot of them got that before dying and I atributed it to bad collection practices. I figured skinny fish were more subject to tramatic injury because they are so skinny. The autopsy of that last copperband showed internal bleeding at the site of the lump and tissue necropsy or dead tissue.
A few days ago I noticed a lump start to form on my new long nose butterly and I knew the fish would die like the others so I caught her and put her in a small tank with some antibiotic which I knew would not help the fish but I figured it would help the water from becomming too fouled when the fish died.
This morning the fish was dead as I know it would be but unfortunately a fish starts to deteriorate rather fast when it is dead. I did however have enough time to do an autopsy on this long nose butterfly.
It too had the same diagnosis as the others and after doing some research I came to a conclusion as to the causes of the deaths of these skinny fish.
Small fish of this type are very thin, the tissue over their bones, especially towards the back where these lesions start is practically non existant and is really just skin with almost no tissue.
This is where the lesions start on most of these fish.
My theory is that these fish, especially when young, when they are kept in a tank are suseptable to
"Methemoglobinemia".
This is not as complicated as it sounds. What happens is that when fish injest nitrate laden water such as in many tanks, the anerobic bacteria in their gut converts the nitrate to nitrite, just as it would do in our substrait.
The blood converts a small amount of nitrite into Methemoglobin. Methemoglobin in small amounts is not enough to kill the fish but it causes the blood to lose some of it's capacity to carry oxygen.
In most fish there would be symptoms like rapid breathing or breathing from the surface. In more severe cases sores form on the head or lateral line from lack of oxygen to those areas and subsequent tissue death, but "I" feel especially in skinny fish it manifests itself in the thin parts of the animal where blood flow would be minimal such as the rear end of those types of fish. Methemoglobitis is not that common in fish from the sea because the nitrate is much lower in the sea.
This disease is also called "Brown blood disease" and it is easy to spot in an autopsy as was the case in these last two fish.
Now I am not a doctor, researcher, neurologist, entomologist, parasycologist, icthiologist, pharmasist, pianist or any other type of ist. I am an electrician with a fish tank. These are just my observations and my theories. I have noticed these lumps forming on most of the longnose and copperbands I have ever lost and I lost plenty of them, probably dozens.
Metheline blue would reverse the effects of methemoglobitis if the fish could be caught but if it is put back in the same tank, itwould probably get it again.
I will continue to research this but I would like to know if any one else has lost these types of fish and if you noticed a lump or sore on the skinny parts of the fish
You can see it start to form in the slightly dark spot near the bottom center of this copperband

And you could plainly see it in this yellow wrasse,also autopsied with the same results.

 

[FunkieReefJunkie]

I think you're onto something with the methemoglobinemia and excessive nitrates. My experience with butterflies though is they are finicky eaters. Mine insists on brine shrimp and searching for amphipods & copepods. I've tried him on clam like others have had luck with, but it's a no go with this particular guy. The one before him starved to death and my nitrates are 0. I recently had a skinny yellow wrasse shipped to me & he died in two days. He should never been shipped out to me in the bad shape he was in. Wonder what the nitrates were in the holders tank was?

 

[Paul B]

Mine eat great, I give them live worms, clams and mysis every day. Usually they get the worms twice. I also feed my tank live baby brine every day. I have a lot of smaller fish.
I can usualy get a few years out of them but they never live as long as most of my fish.
I have found that they get this infliction after a few weeks in the tank. If they go a few weeks, they go for a few years.
In the autopsy, it is easy to see methemoglobitis as it is called brown blood disease.
I am soaking my live worms in methyline blue. It makes the worms last longer anyway and they absorb the medication which reverses methemoglobitis.
Of course I have no idea if that will prevent it but I do know that some of my fish have gotten this so I will try this for a while. I used to always keep the worms in methyline blue just because it makes it easier for the worms to take up oxygen and it prevents fungus. The worms are dyed blue so I know at least some of it is in the worms.

 

[FunkieReefJunkie]

http://en.wikipedia.org/wiki/Methylene_blue#Methemoglobinemia

I've always used it as a dip for new fish but never thought about soaking the food in it. That is a valuable idea.

 

[billsreef]

This disease is also called "Brown blood disease" and it is easy to spot in an autopsy as was the case in these last two fish.

Sorry Paul, but you need to examine fresh blood from a live fish to accurately determine this. Too many changes that occur rapidly at the point of death for a necropsy to determine "brown blood disease". IMO the methemoglobinemia idea is quite a stretch.

 

[Paul B]

IMO the methemoglobinemia idea is quite a stretch.

Bill Old Buddy, you are correct on this last fish because I didn't autopsy it very soon. But the last copperband and wrasse that died of the same thing, I did and found brown blood. But as I said, this is a theory, not a proven fact.
But all the last three fish that died with this necrosis didn't have anything else wrong with them. I just keep noticing that on thin types of fish, they get this tissue death that starts between the bones near the rear end in the very skinny parts.
These lesions start inside the fish and it is not a sore or infection that starts on the outside and goes in.
If you have a better cause, I am all ears, (so to speak)
I am open to theories
You know that I have been doing this a while. I know the causes of fish death but there is something about thin bodied fish getting these dark spots that eventually break through the flesh and cause death. It is not real common but my fish don't usually die from anything else.

 

[billsreef]

Paul,

Are these dark spots something that typically only occur in recently acquired fish (as within a month or so)? Do they start getting a thick brown look to them before the flesh starts ulcerating?

 

[Paul B]

Yes Bill to both and of course not all fish get it. Basically thin bodied fish that are fairly new.
In the autopsy there is also some internal bleeding at the site of the lesion between the ribs. I always see this.
I think the fish dies from infection after the body is pierced.
You can see the picture in the wrasse above. Why? do you have another theory?

 

[billsreef]

I was pretty sure from your description and that wrasse picture that you were describing something I'm all too familiar with. You just confirmed it. It is bacterial in origin. It's a collecting and handling issue, combined with housing in multiple fish from multiple locations in the same systems. The foothold starts in external abrasions that are common to handling. The progression is very slow, sometimes you notice some raised scales at first, sometimes not. Once it gets it's foothold, it works on deep tissue first, leading to that necrotic dark stuff that turns into an open ulcer. Worst part, it is highly drug resistant to any of the stuff we have available over the counter Best part, it is not highly virulent (i.e. infectious to others), and isn't related to water quality in our tanks...if it was a water quality issue it would be older established fish that showed it first

 

[Paul B]

Bill that was my first analysis which I posted about a few months ago about a copperband, but lately I am having my doubts about that.
I thought that because it only seems to occur on the thin sections of the fish.
It seems to come from inside the fish, not from the outside in so a bacterial infection seems unlikely. But the internal bleeding would be consistant with collection practices.
If you look at the two pictures I posted, you will not notice any cuts or missing scales in the skin.
If it happens again I may have to do a more thorough autopsy

 

[billsreef]

Paul,

I've seen hundreds of cases of this, from fresh out of the shipping bag all the way to ulceration and death. It effects heavy bodied fish like groupers just as readily as thin bodied butterflies. Definitely bacterial infection in origin. Just wish I could come up with someone willing to spend the money on some serious histology and culturing for drug sensitivities. Be nice to firmly ID the bacteria involved and find what will knock it out.

 

[Paul B]

The problem with the thing (whatever it is) is that by the time you notice it, the fish is internally bleeding. I have some injectable antibiotics but I doubt that would help.

 

[elegance coral]

I have seen this many times too. I agree with Bill in that this is bacterial in origin. How ever, I believe that water quality plays a major role. Poor water quality increases the likelihood of bacterial infections. It's that simple. Newly imported fish are likely to have a compromised immune systems. Combine the poor immune system and poor water quality with physical damage, and you're likely to get a bacterial infection. Which is what we see in these fish. Until we have an antibiotic, or other treatment, that's effective against this, I believe, the best form of treatment is proper quarantine. It's easier to keep microbial counts lower in QT systems than it is in our established displays, we can eliminate stress and competition form other inhabitants, and it's easier to insure the fish gets adequate nutrition. All of these things will help the fish fight infection.

With all that said, the survival rate I've seen is pretty much nonexistent. I have seen fish survive bruising, but I can't remember ever seeing one survive once the external ulcer shows up.

 

[one clownfish]

I've had my LNB and my little cleaner wrasse for about 3.5 years each. I never go out of my way to feed them. They only get left over scraps when I feed the eel every 2 weeks or so. I haven't had good luck with coral but I've been able to keep some fish for a long time(10+ and counting). My tank is so polluted with N03 (80-100ppm or blood red whenever check it) and P04 from being a FOWLR for so long I'm thinking about starting over. The LNB has been in the tank with 6 very large Tangs and a 7" Emp. Angel, its tough in there. The LNB gets pushed around by the Emp. and Sohal sometimes but when he turns upside down an pokes them with those dorsal spikes, they stop in their tracks and he carries on like nothing ever happened. I'm not knocking any LFS but I only buy my high end fish ($25 or more,lol) from fellow reefers. I've bought to many fish over the years from the LFS just to have them die between 1-7 months for no reason at all. Every other fish is fine but some/most die, I think its from the collection process. Its the exact same thing you posted in your pictures, a little bruise, then always death. I believe some fish aren't going to make it no matter what and others will thrive for years in the same tank with no signs of ick or anything else.

 

[billsreef]

If there is a water quality competent to this, it's from the shipping/holding end. Quite possible ammonia burn, common in shipping, can be the avenue to allow the infection to take hold.

 

[Paul B]

I agree with Bill in that this is bacterial in origin

Sure agree with Bill. :fun5:

I feel that collection may have something to do with it and the fish does die from a bacteria infection but I feel that happens after the skin is pierced. It is unlikely to me that a fish would get an infection on it's inside in the muscle with no external signs of wound.
It starts as a small lump, then turns brown, the brown is from internal bleeding that could come from a trama, but I don't see how an infection would start there.
I know it is from bleeding from the autopsies.
I could also see the fish dying from the bleeding. But not being a doctor,I can't see how an otherwise healthy fish with an operating immune system could get an internal infection.
I could be wrong and I am plenty of times so maybe there is a doctor on here than can answer this. :strange:

One Clownfish, I have also kept many of them for that time period, it doesn't happen to all of them, but I notice it on thin fish mostly.

 

[swcc]

'skinny fish' don't die unless you put them in conditions that lead to their peril....so....water quality...nuff said.. if ya keep killing more sensitive fish, perhaps ya should adapt a better premise for not killing them in the first place(or stop trying) no matter how long the tank has been 'sustained'. what is the major dilemma for reefs in the wild??? eutrophication.

 

[gone fishin]

could it be a normally benign bacteria until shipping gives it the opportunity to cause problems

 

[Paul B]

'skinny fish' don't die unless you put them in conditions that lead to their peril....

SWCC, there are plenty of skinny fish in my tank for years with no problems, I don't keep killing them. Some of my fish are over 18 years old and SPS corals are growing wild so I think my water quality is fine. My other copperbands and wrasses are fine as are delicate bluestripe pipefish and clown gobies.
Most of my fish die of old age which in many fish is about 15. My moorish Idol died in an accident after five years, which for moorish Idols is almost a record.
This thread is just a theory. "Methemoglobinemia" does not usually exhibit like this, it usually starts around the head or lateral line and progresses from there. I am basically just thinking out loud from experience. We don't know all things that kill fish or all things that happen to fish in captivity such as HLLE. Wild fish do not get that, it comes from captivity. It is very common in tangs in captivity but in the 300 or so hours I have spent underwater I have never seen it on a wild fish. What I am proposing is maybe this affliction also may come from either captivity or collection. I do not have all the answers but not everything comes from water conditions. Especially in a 40 + year old tank with over 20 other healthy, spawning, old fish. In the 57 years that I have been keeping fish I have seen plenty of things I can't explain and many of those things are still not explained.

could it be a normally benign bacteria until shipping gives it the opportunity to cause problems

I don't think so, not without a cut in the skin. If a fish or any other animal had bacteria inside it, it would be all over the fish not just in one place.
When we get the flu we get it all over, not just in our nose or lungs and it doesn't cause a lump that eventually punctures our skin. Well it never happened to me anyway. :lol2:

 

[Fretfreak13]

I just wanted to say that you guys are wonderful. This thread is very informative and I think its been a long time since I've seen a debate on anything on one of these forums that didn't turn to petty insults. I don't know much about disease, but I'm definitely following this!

*Subscribed*