THE FACE OF A KILLER Diagnosis and cures for some betta diseases.

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See the red blotch on this betta fry's forehead? It's a killer.

During the first four weeks of my second spawn, I'd only had three fish with a mild and quickly cured case of fungus and one with popeye. I thought I was home free. Then a bacterial infection hit and I lost fifteen fish in 24 hours. The picture above shows what the infection looks like.

The morning of March 26 I noticed a few of the fry had what looked like a trauma to the forehead. It seemed like something caused by swimming too fast and crashing into the filter. Bright red blood marked a roughened area. The next morning four fish were dead. By that night eleven more would die. I quickly ran to the disease guide on the Betta Talk site and diagnosed the problem as one of the deadliest illnesses a spawn can have: a bacterial infection. It is very contagious and, as I had already found out, a quick killer. I'm using tetracyclin to treat it and will update this page as to how well it works.

This occurrance highlighted three disease issues for me: (1) Because of the difficulty of photographing fry, there are few pictures of diseased fry to help betta raisers identify diseases; (2) While most betta sites recommend treatments for diseases, I have yet to find one that gives detailed information on the problems with using them and anicdotal cases how well these treatments work; (3) I have never seen a statement on how many disease outbreaks, and of which kind, a typical spawn has. This last issue is important to people like myself who are new to spawning so they know if they are having an acceptably normal series of problems or if most spawns are completely disease free, indicating that they are doing something very wrong.


NEW!!! Please see below for Tammy S.' account of curing a case of dropsy, a fatal disease that's supposed to be uncurable in bettas.


What follows is a chronicaling of my second spawn to provide an example of the type of information needed.

Basic conditions and care: I used tap water treated with 1 tablespoon of aquarium salt, 15 drops AmQuel, 15 drops NovAqua, 3 drops Aquari-Sol, 8 drops MarOxy, and 2 drops of Vitamix Plus for every 2 & 1/2 gallons. Water temperature is maintained at 79-82 degrees. I feed the fry vinegar eels and baby brine shrimp. I thoroughly siphon the bottom of the tank every third day and replace 95 percent of the water. My biggest failing is a tendency to overfeed.

Fugus outbreak: The fry were two weeks old when I noticed pin-point white spots on the tails of three of them. I diagnosed (guessed) it was fungus and treated it with Aquarium Products Anti-Fungus treatment. Within 48 hours all signs of the spots were gone leaving only small holes on the edges of the fins where they were. One week later the fins had grown back. The fungus never returned. The instructions on the bottle failed to say how long to use the product and the medicine turned the aquarium sealer in the tank blue.

Popeye outbreak: Four weeks into the spawn I noticed that one fry had red rings around his eyes. The next day his eyes were bulging and he swam in rapid, nervious circles. He panted for breath. I started treating the entire tank with Ampicillex by Aquatronics. This is a white powder. Most of it fell to the bottom of the tank in large pieces that were very slow to dissolve, even with gently stirring and trying to crush the pieces with the stirrer. All of the fish seemed to be less active and have less appitite under this medication, but this is a very weak subjective observation. I can't say whether the medicine worked bacuase the fish died during the third day of treatment. The popeye could have gone too far or the fry may have succommed to a bacterial infection that hit at the same time.

Bacterial infection: Four weeks into the spawn I noticed red rough splotches on the foreheads of four fish: bacterial infection. By the time the disease had run its course, half of the fry had died. The treatment of repeated 100-percent water changes coupled with tetracycline stopped the infection. However, I got the impression that all the medicine did was prevent uninfected fish from catching it. All the fish exhibiting visible signs of the infection died. The high mortality was almost certainly my fault because I failed to spot the first case. The infection grew in the tank for six days before I figured out what was going on. Had I started treating the fry sooner, I'm sure many more fish would have been saved. The lessons I learned was what bacterial infections look like, start treatment immediately, and most importantly to add some methylene blue to the spawning tank's water as a preventative.

Mr. Dean Carstensen's warning about Algae Destroyer!

On 12 March, 2004, I received the following email from Mr. Dean Carstensen:

I was reading about your Betta raising experiences and noticed that you regularly use Algae Destroyer. I am a Guppy Breeder and have had entire tanks of fry die almost instantly after adding Algae Destroyer to the water. I did not overdose; I used exactly the recommended dosage.

I did some internet research and apparently some species are very sensitive to Simazine, the active ingredient. Even when it doesn't kill fish, it has been shown to stunt their growth.

Here is a link to the most informative page I have found so far on the toxicity of Simazine:

Dean Carstensen

I haven't noticed any problems with my bettas, but Mr. Carstensen raises an important caution and I hope everyone reading this will give it serious consideration before using Algae Destroyer. I would very much like to hear from anyone else with information about this. Thank you.


Experimental dropsy treatment!

(Note: although I, like many people, refer to dropsy as a disease, it is in fact the name for a symptom or condition. The actual disease is most likely a bacterial infection of the kidneys. This name confusion is similar to the term "shin splints," a name used like it is the disease when it's really only a lay-term for symptoms related to any of a wide range of muscle/tendon/ligament/bone inflammations associated with the lower leg.)

March 5, 2003: My daughter had a fish with dropsy so she gave me permission to attempt a novel treatment. Here's how it went:

Dropsy is considered an incurable, always fatal disease. No one knows what causes it. Experts even disagree on whether it's contagious. The recommended treatment is tetracycline, but according to Faith at the Betta Talk site, this seldom works unless the treatment is begun at the earliest indication. Such was now the case with my daughter's fish. The abdomen is severely blotted and the scales are standing out.

The fish spends most of its time in an extreme head down position, as if it can't empty its swim bladder of air. It will repeated drift to the surface tail first.


The most prominent symptom is the bloating of the fish caused by excess liquid build up in body tissues. This bloating makes the fish's scale stand out like a pinecone. It's not known if this bloating, an inability to feed, or some other agent kills the fish.

The experimental treatment I'm trying consists of two parts. First, a massive dose (5 times the recommended amount) of tetracycline to fight the disease. Second, immersing the fish in a highly saline solution to use osmotic pressure to draw excess water from the fish's tissues.

My reasoning is that while tetracycline may cure the ailment in time, the stress caused by bloating kills the fish before the medicine can work. Drawing some of the fluid out of the fish may give it enough time to be cured.

It is important for anyone reading this to know that I am an untrained lay person as far as fish diseases and treatments are concerned. It is very likely that my assumptions are grossly incorrect and that the treatment will fail.

Please check back in a couple of weeks to see how it worked... and please wish me and Delin (the fish) luck.

Update: I discovered that Elena, the fish borrowed from my sister in law to spawn with Snow, also has Drospy. It appears to be more advanced than Delin and since Elena was in the tank before Delin, the assumption could be made that Elena got it first and passed it to Delin. The question now is: Since Snow was in the tank with both fish, why didn't he get it as well?

Update: After pondering this last question most of the day, I came up with a possible explanation for what causes dropsy. If I'm correct, my treatment won't do any good.

Consider the following:

1. The fish I borrowed from my daughter, who lives across town, and reported as having dropsy had been in a jar with another female betta for eight months. After my moving her to my house the fish developed dropsy in two weeks. The female betta my daughter kept is still healthy.

2. Prior to using the sick female mentioned above for attempting a spawn, I had borrowed and attempted a spawn with a different female borrowed from my sister-in-law. This female was also in a jar with another female, as it happens, her sister. After discovering the first case of dropsy I checked all of my other fish. They were all healthy... except the female I borrowed from my sister-in-law which also has dropsy. The sister that she kept, the one I didn't borrow, is still healthy.

3. The male that I attempted to spawn with both females who now have dropsy appears healthy with no trace of the disease, even though he had been in a tank with one for a week and the other for two weeks.

4. All of my 22 other bettas are healthy.

5. Both females that got sick had never been spawned before and were over one year old, which is very old for a first spawn.

6. (This is the really interesting part.) The sick female I borrowed from my daughter and the sick female I borrowed from my sister-in-law are also sisters. They were both from a spawn I had last January that I gave away to friends and family.

What all this suggests to me is that dropsy might be an inherited disease that is activated by stress. Both fish that got sick were sisters. Both had been subjected to great stress by being moved, removed from long-time companion fish, and for the first time placed in a tank with a male. The fact that the one sister who wasn't subjected to stress did not get dropsy supports the stress-cause theory.

If this theory is correct, it would explain why no one has been able to identify the cause... because there isn't any, at least nothing external like a parasite or dirty water. It would also explain why treatments always fail: they aren't effective at dealing with a genetic disorder.

(I'd like to take credit for this idea, but actually it was my sister-in-law, Carol Beyer, who suggested it.)

UPDATE!!! Both fish died. I spoke to Faith at Betta Talk and she said that the current belief is that dropsy is the result of kidney malfunction caused by a bacterial infection. Treatment is difficult because there are many different bacteria that can cause the problem and the treatment for each varies. Stress may weaken individuals and make them more vulnerable.


NEW!!! Possible Dropsy Treatment!

On 31 October, 2003, I received the following email from Lorena Hazama who successfully treated two bettas who had dropsy:

From: Lorena Hazama


I'm in no way any kind of expert, but I just wanted to share what I learned

from a dropsy episode with my fish with the hopes of perhaps helping someone

else someday. When my fish first got it, I didn't have any hope, because I

had heard that it was difficult to cure.

With a lot of help and suggestions from people a betta forum, esp. Uptongirl

and Violetedawn, as well as some other resources, my fish's case of dropsy

has been diminished if not "cured".

Have no idea what caused his kidney function to fail/decrease. I'm guessing

it was bacterial or viral because Kanacyn seemed to do the trick.

Treatment was in stages as I changed things as I found out about stuff. I

have no clue what actually helped--or if it was something I should not have

done--so I'm putting everything here:

1. Had him in Maracyn II for about a day.

2. When I got Kanacyn, I put that in the water instead (did not use the 2


3. Tried to keep temp as warm as possible--was a bit difficult because we

have air conditioning and he's at work. Some sites say they upped the water

temp to 86C for gold fish. I think his water was probably around 70-72C. But

if you're changing temp, please do it slowly as not to stress or harm your


4. Shielded his tank from stressful light by making a black paper "box" with

some air and peep holes cut out. This really seemed to help.

5. Added some epsom salt to his Kanacyn water. (1 tsp for 5 gallons of


6. I was changing his water every other day--100% change. I also kept the

water for changes in the same room as the fish tank so it would be about the

same temperature when I changed his water.

Notes: The epsom salt helped his swelling. I was so afraid that he'd burst

or something he looked so swollen. I'm sure he probably felt more

comfortable, too.

Read medication instructions carefully and follow them to the T. It mentions

not combining with other chemicals unless compatible with the medication.

This is really important! I used only Kanacyn and epsom salt together in

untreated tap water but I could get away with this because our tap water is

drawn from artesian wells and is not treated with chlorine. So I didn't have

to use water conditioners or anything to prep his water. I would not

normally do this, but I wasn't sure if the chemicals would combine OK with

the medication.

If you have to treat your water, you might want to get help from someone

who's a lot more knowledgable about water conditioning.

If you're like me and don't have a 10-gallon tank or water vessel to put

your medicine in, we came up with the following:

1 capsule of Kanacyn and 2 tsp of epsom salt were mixed in 10 Tbs of water.

We then used the ratio of 1 Tbs of concentrate to 1 gallon of water for

water changes. We kept the concentrated Kanacyn/epsom mixture covered and in

a dark place just in case. This may not be the best way to do this, but it

seemed to work OK.

My fish didn't show improvement until after the epsom salt, so it was about

a week from when I noticed the dropsy and started treating it to see

results. His recovery sped up more after that. So, even if you don't see

results right away, just hang in there and give your fishy time to try and

kick whatevers ailing him.

Like I said before, I'm not an expert, not a breeder. Not even an experienced

fish owner--I've taken care of a grand total of 4 betta! But for whatever

reason, my fish and I were lucky enough to, with lotsa guidance, to be able

to kick this.


NEW!!! A Second Possible Cure of Dropsy!

Tammy S. sent me an email stating that she cured her betta of dropsy using a technique similar to the one above. Initially, her fish stopped eating and tended to float to the top of the tank. After a dose of maroxy he started eating a little but was still floating a lot. The next day he started showing the bloated, pinecone symptoms of dropsy.

She began treating him once a day with maroxy and twice a day with maracyn II for one day every five days. This continued for 10 days. The temperature was maintained at 70-72 degrees F. and the fish was kept in a dimly lit corner. The water was changed every other day.

On the third day of this treatment she started adding Epsom salt at the rate of 1 teaspoon in 5 gallons, using prtreated water like normal.

One week after adding the Epsom salt the fish started improving. After that he recovered quickly. Tammy also stated that she regularly exercised her fish by showing it a mirror a few minutes every day. As of two months after the treatment the fish is alive, strong, and showing no signs of dropsy.

While annicdotal accounts can never replace scientific data, the above two cases suggest that in the abscence of more informed guidance there might be hope for bettas with dropsy. If you have a betta with this disease and extensive research turns up no scientifically verified cure, you might want to give this treatment a try. As with all diseases, a critical factor is early detection and medication. Left to linger for even a few hours, a fish can sustain enough damage to his or her internal organs that even if the disease is cured, the fish may still die. Also, I have read that Epsom salt has sulfer in it so there may be problems using it with sulfa-based medications.

On January 26, 2003, I received an email from Kate who said she cured a bacterial infection in a spawn by treating it with Kanacyn. The infected fish survived, which is better than mine did on Tetracycline.

I discovered a new disease! (sort of)
At the same time a bacterial infection attacked the tenth spawn, several fish appeared to be trapped on the surface of the water, they couldn't swim down. They'd make a dash half an inch downward then bob to the surface. I thought it might be an effect of the infection. Actually, it turns out I'd started a fine bubbler at the same time and a few of the fry had swallowed bubbles thinking they were food. The air in their stomachs pinned them to the surface. They all got over it within a few hours. I call this disease air-bubble-itus.


I only have three so far. If you have any you can contribute, please do so. They need to be large and sharp enough to help people identify the problem.


Protruding scales and a bloated abdomen suggest the fatal disease dropsy.


The first symptom I noticed was a red ring around the outside of the eyes. It looked like the fry had been in a fight and was getting black eyes. The next day both eyes were protruding. He was panting and when disturbed would swim in rapid, nervous circles.

Another example of popeye, this time in an adult fish. This is Honey, the fish mentioned in the "My Bettas" page as having some of the symptoms of dropsy. She's gone through a one-week treatment with Ampicillex, which cured my earlier popeye outbreak, but hasn't gotten any better. Now I've started her on Tetracycline. Wish me, and her, luck.

Bacterial Infection

Roughened, bright red blotches on the forehead. I've read that these may appear elsewhere.

An invisible killer unmasked!

When the bacterial infection was at its worst, I noticed that the water would turn cloudy within hours of a 95-percent water change. It occurred to me that the cloudiness was nothing less than the bacterial bloom itself overrunning the tank. That night I darkened the fish room and shined the focused beam of a 5-cell maglight through the water. Instantly, pale blue-green eddies of death swirled an inch from my eyes. I managed to capture this killer on film. At the time, it struck me as ironic that something so pretty could be so deadly. By the time I had taken this picture, these green whorls had killed twenty fry.

Unknown Condition/Disease

Two of the fry have had large transparent blisters on their sides since they hatched. Other than being much smaller than the rest of the fry, they seem to be healthy. The fry in the photo was purposely overexposed. The bubble is virtually transparent and to capture it I had to flood the subject with light. I have no idea if this is a genetic deformity or a disease. I would greatly appreciate an email from anyone familiar with this condition to tell me what it is. Thank you.

Unknown disease!

Nine weeks into my second spawn, one fry picked up a red fuzzy patch near the base of his tail. The color suggests a bacterial infection whereas the fuzziness suggests fungus. I isolated it and am treating it with Neosufex, a broad spectrum anti-fungal/anti-bacteria medication. Four days into the treatment the fuzziness and color seem to be fading. None of the other fish appear to be infected. I would greatly appreciate an email from anyone familiar with this condition to tell me what it is. Thank you.

NOTE: A week later all signs of the patch had disappeared and the fish have remained healthy.


Melafix effectiveness!

Sarah Liu reports that Melafix is effective for helping fins heal but not for fin rot.

Louis Foxwell, a breeder in Florida, had this to say about bacterial infections: "... do a 100 percent water change. Just watch the temp and Ph. keep them close. You are right about the problem being bacterial. It shows up frequently with fry. They will develop redness around the head. I spoke with a fish vet about a month ago about this very condition. The water change was her recommendation. I tried it and had immediate good results. Be very careful with meds for babies. they can not tolerate most medication. I use malachite green for fungus and methlyne blue for bacteria. Both is small doses for fry, 1drop per 2gal. The difficulty with bettas is that the babies tend to create a dirty tank."

Kelly Utter says she cured a case of velvet by daily 70-percent water chages coupled with 3/4 dosings of "Quick Cure." She ended up with losing ten precent of the fry but the rest were cured. The treatment lasted five days.

Alex Tseng said that when he quit feeding his betta worms, they stopped having a wide range of disease outbreaks.

Thanks Everyone! Anyone else have a suggestion?

What interested me most about Mr. Foxwell's comments was his saying that bacterial infections in betta fry are a common problem. I found this a relief because it means that just because my fish got one, I'm not necessarily a bad fish keeper.


NEW!!! Algae Destroyer and Fungus Eliminator tested!

The fry tank for the fourth spawn started showing a cloudy growth covering the bottom and all the filter equipment inside the tank. After consulting with a few website friends (thank you, guys!) the growth was diagnosed as brown algae. A pet store recommended Algae Destroyer by Aquarium Pharmaceuticals. I added a teaspoon and within a week the growth was greatly reduced, even though I didn't do a complete water change. While there is still some growth on the bottom of the tank, this product seems to have helped significantly.

My red female betta, Juliet, developed two small patches of cottony-like growths on her body: fungus for certain. After gently wiping the patches clean with a cotton swab, I did a complete water change and added 1/8th teaspoon of Fungus Eliminator by Jungle (yellow crystals) to her 3/4-gallon jar. This treatment was repeated after four days. Four days after that I placed her in unmedicated water and after two weeks there is no sign that the fungus has returned.


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