Why Did My Betta Die?

[qoftheq]

A few months ago I bought a white double tail betta at a very nice, healthy fish store. I set him up in a 5.5 gallon with a filter (current diffused) and lots of plants. He seemed well enough, until recently when I added three small corydoras to his tank (temporary, the 40 gal wasn't quite cycled yet and they were a rare line I wasn't likely to see again). I noticed he was getting listless and I figured that the overly active corys were stressing him, so I moved them out. He got a bit better, but two days later I found him dead at the bottom of the tank byebye. I constantly checked his water stats, and his tank was completely cycled. The nitrates never build up cause its so heavily planted, but I do regular small water changes anyway.

A few things I figured could be important:
- I feed live Tubifex worms. My eel, who also ate them died within a day of the betta. HOWEVER, I had not fed the betta tubifex for at least a week AND all of my corys ate the same tubifex and as of now have suffered no ill effects.
- My tank goes cloudy, first an odd whitish cloudy then free-floating algae blooms EVERYWHERE. This happened in my cory tank and went away once I replaced the carbon. It happened in my betta tank and I replaced the carbon with no change. It eventually went away on its own only to come back a few days before the bettas death.
- The water in my area is EXTREMELY soft and acidic, so my friends and I have developed a method of putting crushed coral in a sock and hanging it inside the tank. I test the water regularly and moved the sock out of the bettas tank when I noticed it was getting a little more basic then I would like. The water chemistry changed over about a month and a half.
- My betta ate the snails in his tank. I figured them for a decent live food.
- For a good week before his death, my bettas stomach looked fairly large. I figured it was because he was eating all my snails. No other possible signs of illness.

Thanks a ton for your help! I would like to eventually get a new betta, but I don't want to introduce one into conditions that could possibly be hazardous to it.

 

[zoekin8yg]

if the bettas stomach was swollen it could have had dropsy which is a sign of internal problems. were its scales sticking out?

 

[Jaded12]

Hmmm, when you found him dead how did he look? Did he have and fungus anywhere (white cotteny patches) were his scales sticking out in a pinecone effect? was his spine bent akwardly in an "S" shape. How big was he? Any idea how old he was? If he was at a pet store chances are he was at least a year old, probably older. Was he swimming normally before he died? or did he tend to float slightly vertical head up? Answer these and lets see what we can figure out

 

[MarleyBetta]

maybe the corydoras where carrying a parasite or something
or the snails could have had something

 

[qoftheq]

His scales were not sticking out. I've seen dropsy before and this didn't look like it. His spine wasn't bent awkwardly, and I'm not sure about the white cottony patches but he did seem to decompose AWFULLY quickly. He couldn't have been dead more than three hours when I found him and he was already partially decomposed. Now that I think about it he did seem a bit fuzzy, I just figured it for normal decomposition. I did notice before he died that he would stay in the same place on the surface, and occasionally list to one side and not make the effort to right himself.

Thanks!

 

[Jaded12]

Hmmm, there's a possibility he had some kind of internal infection. But to me its sounds like he may have passed away from old age. I've had 2 bettas that passed away from old age both of them in there final days stayed in one spot, floated up vertically with there head up and made no effort to right themselves. Most pet store bettas are a year - year and a 1/2 old when you purchase them, and the average life span of a petstore betta (due to the conditions they're kept in before they're purchased) is only 2 - 3 years.

 

[qoftheq]

Well, this is an extremely nice fish store. They order thier bettas from nice, reputable breeders and the tanks are always clean. This is the only pet store I've ever been to where you go tell them that one of their bettas looks distressed and they go "oh no!" and run to the betta display. I only had him for a few months, it seems unlikely that he was that old.