View Full Version : Mysterious betta death

08-11-2009, 08:31 PM
I know it's all part of the game, but fish loss disappoints me. Most of the time fish death can be attributed to improper care, less than ideal water conditions, aggression, disease, or old age. In each case it can usually be determined which factor came into play, but not this time.

My male betta had been in my 10g. planted tank for a few weeks, along with a few danios and rasboras. Up until last night he had been eating fine and looking healthy. I noticed him hanging out at the bottom near a plant during feeding time today, not coming up for food. I gently nudged him and he did swim, but not much. Did a 50% water change just in case, and by the time I was finished, less than 10 minutes, he was dead. He looked perfectly healthy when he died. Fins were in great shape, no marks or discoloration, no signs of disease. So what killed him?

I came up with a few ideas; he ran into something pretty hard and caused internal damage, toxic plants, or a fish coronary. Either way, I'm not happy about it. By the way, all the other fish are fine. Just a fluke? -Lp

08-11-2009, 08:33 PM
How old was he? Was he bulging in the stomach? couldve been constipated. Also I doubt he hit the glass hard enough to cause seriouse damage.

08-11-2009, 08:34 PM
Sounds actually a lot like a swim bladder burst. That's my theory.

08-11-2009, 08:45 PM
One other idea. I've heard that sometimes drastically changing the very water chemistry that is making the fish ill can actually make matters worse. Their internal systems have been slowly changing over time to accomodate the water. Then if you do a large water change, especially when they're already ill, their system cannot adapt that quickly to the new parameters and they die. When there is toxic danger such as a very high ammonia content or other toxin that has leached into the water, a large immediate water change is recommended because the fish would certainly die, and least you may have a chance of saving them. However, in a situation where only one fish appears ill, smaller water changes over several days is usually a better choice. My 12 year old's betta died a month ago for that very reason. He'd let the water get bad and didn't tell me. Then he changed half of the water by himself, and within hours his betta died.

08-11-2009, 08:46 PM
I'm unsure of his age, but I bought him less than a month ago. How long do they keep them in the lfs, I would imagine the turnover rate is quite high? Also, his stomach wasn't deformed in anyway, in hindsight, I should've taken a picture. If his swim bladder did burst, would it inflate his stomach, or just the opposite? I'll probably never know for sure, but it'd be nice to eliminate certain factors. Thanks!

Edit: Kath, that sounds plausable, a small water change would've probably been better.

08-11-2009, 08:47 PM
Sometimes with bettas they bloat with the swim bladder, sometimes not. It's just my theory, not a solid answer. This is a pretty strange death, I have to tell ya.

08-11-2009, 08:52 PM
Well, it's a good theory and one I didn't think of. Thanks!