So, I've been having problems with my 30 gallon. I don't know what it is. The fish turn black, gasp, then die. All happens within 24 hours. It's happened to my ram, and the new krib I put in after that. Strangely, though, it's hasn't affected my orange cories or angelfish, which are the only fish left in the tank.

So... I was thinking I'd hit it with some quick cure or metezendiderol (that is spelled way wrong, but if you sound it out you should get the gyst) for a week, then doing 2 50%ers 2 days in a row.

Or, I could drain it, put black sand in, re-cycle it, and put in a trio of electric yellow labs and a pleco, or something. The problem is that I'd have to get rid of my angel, which I really like. It's sorta like a pet now.

Once I put in the yellow labs, though, I'm really limited to any variety of fish.

So, tell me what you think?

Whoops.

Thanks,
-Stu

How long has this been going on?

Cories seem to be really resistant to disease. I have never had a cory get sick. I had one episode a while back in a tank where every fish got ick except the cories. I have one old peppered cory who was given to me while my first 10 gallon was in the process of cycling, he's still alive and kickin' in my 29 gallon! I have 7 cories in the 29 gallon now and they are all very active and social.

It may not be neccessary to totally start over. I'll look in my disease book and see if I see anything.

Culumnaris is my best guess of the problem based on the information given. I know that this disease can kill rather quickly. What temperature is the tank at?

This mainly describes symptoms for the slow-killing strains of this disease, but there is a strain that kills very quickly with very little warning. I have read of some people describing dark black or grey appearnce before death, but there are so many symptoms and different strains. You might do some additional research. Here's a very basic article-


Aquatic-Hobbyist disease articles
Flexibacter Columnaris

Columnaris is a disease caused by the bacteria Flexibacter columnaris, a long, thin, rod shaped motile (capable of movement) bacteria. The bacterial clumps form microscopic columns or dome shaped masses, hence the name columnaris. Two years ago I rarely read about this disease on fish forums, now it is getting more and more common.

Symptoms: Symptoms of this disease include grayish-white spots on some part of the head, fins, gills, or body usually surrounded by an area with a reddish tinge. The columnaris lesions on different species of fish vary in size, location, and appearance. These may appear thread-like, particularly around the mouth, giving rise to the incorrect name of 'mouth fungus'. Characteristic lesions can appear on the back, the fins, gills and belly. Catfish, in particular, tend to have lesions on their bellies and sides. Fins will deteriorate and sores may appear on the body. The gills may be affected, giving rise to bacterial gill disease. It may cause 'shimmying' behaviour in fishes, particularly livebearers. Mollies, for some reason, seem to be particularly susceptable. Although columnaris most commonly involves external infections it can occur as an internal systemic infection with no visible external signs.

Columnaris is often mistaken for fungus, as most of us are taught that white fuzzy growth on the skin of a fish means fungus. However, white or grayish white, fuzzy looking lesions on that occur on normal skin, mouth or fins - especially with a bleaching of the skin underneath - fish are much more likely due to columnaris. True fungus generally grows on infected wounds or torn fins, that is, it grows on dead tissue.

Causes and Course of Disease: Columnaris is opportunistic and strikes when a fish is stressed. Poor water quality, sudden changes in conditions, wide temperature swings, high nitrate concentrations, low dissolved oxygen concentration, crowding, shipping, and bullying can also trigger columnaris. Columnaris will be more virulent in temperatures above 77 degrees. My LFS tells me that summertime is "prime time" for this disease and they almost always suffer significant losses when fish are shipped in warmer weather. Hard water with a high Ph seems to accelerate the course.

Under appropriate conditions columnaris can spread rapidly and cause catastrophic losses. One strain has a virulence that is low and it takes a few days to kill the fish. On the other hand, the highly virulent strain will kill a fish in under 24 hours. If your fish has the highly virulent strain, there is not much that you can do to stop it or treat it. These fish often die so quickly that there may not even be enough time for them to show any external signs of infection.

Treatment: First, slowly lower the temperature in the tank to 75 or 76 to slow the course of the disease. Also, since columnaris thrives in low oxygen conditions, the addition of an airstone or lowering the water level to create more splash from the filter will also help.

The most effective treatment for columnaris if the fish is still eating is medicated food containing oxytetracycline. Aquatronics makes such a food, as does Zeigler. Often, however, the fish is not eating by the time symptoms are noticed. Antibiotics in the water would be the next treatment option. Erythromycin (Maracyn), nitrofurazone, nifurpirinol, acriflavine, chloramphenicol or tetracycline can be used to treat the columnaris itself. However, a fish infected with columnaris often falls prey to a secondary infection which is resistant to both of these. Therefore, a combination of Maracyn and Maracyn Two or tetracycling and kanamycin is recommended. CONTINUE TREATMENT FOR A MINIMUM OF 10 DAYS.

I should note here that resistant strains of columnaris are cropping up on both sides of the Atlantic. We currently have nothing that will treat it. Strict quarantine measures should be maintained with ALL new fish. It's hard enough to lose a new fish, but to lose old friends is somehow worse.

Here's a much better link with some pictures.

culumnaris pictures and facts

Thanks for the excellent info.

Well, this sucks. Looks like I have the mutant strain, of which there is no cure.

I suppose I don't have much of a choice but to get rid of my angel, because it is now carrying the disease, and any other fish I put in there would also get the disease.

Am I thinking right?

Thanks,
-Stu

Treatment: First, slowly lower the temperature in the tank to 75 or 76 to slow the course of the disease. Also, since columnaris thrives in low oxygen conditions, the addition of an airstone or lowering the water level to create more splash from the filter will also help.

The most effective treatment for columnaris if the fish is still eating is medicated food containing oxytetracycline. Aquatronics makes such a food, as does Zeigler. Often, however, the fish is not eating by the time symptoms are noticed. Antibiotics in the water would be the next treatment option. Erythromycin (Maracyn), nitrofurazone, nifurpirinol, acriflavine, chloramphenicol or tetracycline can be used to treat the columnaris itself. However, a fish infected with columnaris often falls prey to a secondary infection which is resistant to both of these. Therefore, a combination of Maracyn and Maracyn Two or tetracycling and kanamycin is recommended. CONTINUE TREATMENT FOR A MINIMUM OF 10 DAYS.

http://www.aquatic-hobbyist.com/profiles/d...columnaris.html


you could do this however if you have the high speed killing virus there doesn't seem to be anything that can help you

I allready read that, too. I'm thinking it is the fast one because 1, they die in 12 hours, and 2, they don't have any physical appearance problems except that they turn dark and gasp.

Did you buy the tank used? Have you checked your ammonia and nitrite levels? Could a chemical have gotten in the tank? Windex, etc. Hmm... trying to think of some other possibilities. Have you added any new fish? What is your pH at? However I don't think a high pH would turn them black and kill them.

Good luck stewie. I'll keep researching and let you know if I find anything. Keep us updated.

Tank was new, and about 8 months old. Ammonia and nitrate perfect. Ph is 7.0

The symptoms for the fast-killin strain that cannot be cured are that the fish turn dark, gasp, and die within 12 hours. That is exactly what happened to my fish.

So, you say treat it with some maracyn and maracyn 2, right? No, because the resistant-fast-killing-strain has no cure.

Why my angel hasn't died, along with none of my other fish, I have no idea. I may think that they got over it, and are now immune, somehow. Of course, now I can't get any new fish because they'll die in the first couple of days right away.

So, I'm stuck with 1 angelfish and 2 corycats in 1 tank for the rest of it's days unless I get rid of my fish. But, I couldn't trade them into the LFS because I think their carrying the disease, and I don't want to give the LFS's fish it.

Here is an article from fish pharmaceutical website that discusses lifespan of the bacteria:

Flexibacter Columnaris can persist in water for up to 32 days when the hardness is 50ppm or more, but a hardness of 10ppm reduces viability considerably. The addition of carbon to the system increases the survival of this disease in hard water, but this is not the case in soft water.

Columnaris is prevelant in systems with high organic loads, crowded conditions, handling and low dissolved oxygen content. Lesions generally develop in 24 to 48 hours following handling, followed by death at 48 to 72 hours if not treated.

I wouldn't get rid of the fish just yet, I'll try to find some other info.