betta fish with mouth fungus?

Question
QUESTION: I have a betta fish that seems to have developed mouth fungus. Yesterday he was completely fine, and this morning when I fed him I didn't notice anything out of the ordinary. But later in the day I glanced inside the tank and couldn't find him... turns out he was hiding in one the decorations. I got him to come out & he seemed fine still. Then a few hours later I noticed that his mouth was completely white & there looks like there's some more white patches springing up around his tail. He's really lethargic and won't eat. I had to use my fish net earlier to tap him just to see if he was alive because I couldn't tell if he was breathing...

I've only had him for about four or five months, so I don't think his age would be contributing to this. I recently moved him from a bowl that was a little over a gallon into a 10 gallon aquarium. I have a 50 watt heater that keeps the tank between 80 and 82 degrees, and I'm using the filter that came with the tank (I'm not sure any of the specifics on it other than it's by Top Fin). I also treat the water with aquarium salt with every water change. He's been in there for about a week now, and I just added some danios two days ago. I bought three, but one died yesterday. I don't know why it did, I just assumed it was sick when I bought it. The other two seem fine though. The ammonia and nitrate/nitrite levels are normal (ammonia tests show 0 ppm & nitrite is at 0 ppm & nitrate is between 20 and 40 ppm). The other fish seem fine.

I treated the entire aquarium with Maracyn and Maracyn-Two. I'm not sure if I should remove the betta, or treat all of the fish. And I don't know what the proper treatment would be for this situation. I used the Maracyn products because that was the only medicine I have on me right now & it's worked in the past with other ailments my bettas have had. Any help would be much appreciated!

ANSWER: HI Jessica,
  I assume that it isn't ick -- do you know what ick looks like (tiny white spots all over the body)?  

  Fungus around the mouth is often the result of damage due to fighting but that wouldn't explain the tail fungus.  

  It is possible that the danios brought in some weird fungus.  It's really hard to say from here.  

  Have they responded to the treatment at all?

-- Ron  
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


---------- FOLLOW-UP ----------

QUESTION: Yeah, I'm sure it's not ick. But it does look like the treatment is helping. He's perky & has an appetite again. And it seems like the fungus around his mouth is starting to go away (I can actually see patches of white stuff come off of his mouth). But where the fungus was is now just red, it looks like an open wound. I'm not sure if that's normal. And he also lost his top fin. The day after I began treating the tank it turned black and fell off in bits. Now there's less than a half-inch left. But since that one day where the fin fell off I haven't noticed any more signs of fin rot. I also haven't noticed any more damage to his bottom & tail fin from where they were tearing before.

I have a feeling that the danios are the cause, which is why I decided to treat the whole tank instead of just the betta. Today is the last day for treatment. I'm planning to do a 25% water change tomorrow and then repeat the treatment again after a day or so because the betta still has some white patches around his mouth, though it is looking better.

What steps would you recommend taking in the future when adding new fish? I would like to eventually add a few more fish, but I don't want my others to get sick every time a new one shows up.

Thank you for your help & for taking the time to read this.

Answer
Hi Jessica,
 It is very hard to get rid of infections in a fish tank once they are introduced, so the best thing to do is to try very hard not to introduce them in the first place.  

 The best thing you can do when buying fish is to buy them from a good fish store.  Walk around the store and look to see if you spot any dead fish.  If you see dead fish in the tanks, don't buy anything there, no matter how much you might like a particular fish.  

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>