Dying Bettas...

[Nippy Fish]

I've been keeping bettas for years, but I just had 2 die from the same tank and I can't figure out why. I had the first betta in a 20 long planted for a couple of months, all is well, then one day he's suddenly dead and so are two corycats. All of the other fish are fine and thriving. I tested the water...ammonia 0, nitrites 0, nitrates 10. I change the water 40% every 10 days.

I waited a few days, decided it was a fluke, and moved one of my other bettas from a smaller tank into the same 20 long and within a few days without any signs of illness or stress he and another fish were suddenly dead. Both of these bettas were show bettas from a highly reputable lfs.

Then, the next day, a third betta in a different tank (a Petsmart betta) was dead. No warning, no signs, just dead.

There is no stress in the tanks whatsoever, nothing has been going on with the tanks at all, nothing added, nothing removed, nothing changed. There are no predators, no bullies. They eat a varied diet, something different all the time. No vast temperature changes. I just can't imagine.

Any ideas? I'm afraid to get another betta.

 

[joy13]

The first thought that came to my mind was something was sprayed near your tank, then I saw you had other fish in there and they most likely would have been effected too.

 

[MichaelsLilGray]

unfortunately there will be no way we can tell you whats wrong here.. to many variables...

 

[HooKooDooKu]

...
Any ideas? I'm afraid to get another betta.

First, its interesting to note that you DO list other fish (beside just the bettas) dying... it's just that you list other fish that are NOT dying.

Second, at the risk of sounding callus... pet store bettas are less than $5, so if you still want bettas, I don't see it being a big deal to get another one since you're not exactly risking much if it dies.

However, before adding another betta, I would do at least two things:
1. Clean the tank as best as you can doing a 100% water change, or several 50%+ PWC to effectively try to "rinse" any unknown substance that could be harming bettas out of the tank.
2. Purchase the betta, but keep in in a QT for three weeks. That will give him a chance to de-stress and give a chance that any possible betta specific diseases die-off in the tank.

Of course the other thing to do in the mean time is look for unexpected sources of the deaths... namely the other fish.

The idea is that you go into it with the notion that the betta MIGHT die (so you don't want to go spend the money for a show betta), but at the same time you're doing everything possible to prep the tank such that there is no reason the betta should die so that we're not going through this experiement just to kill another betta.

The other thing you might want to do is for the first day or so the new betta is in the tank, closely monitor the tank (most the day, and check on it a few times even in the middle of the night... perhaps set up a video camera that can record with IR in the dark).

 

[joy13]

I believe this is the list of fish he has in his tank

1 Black Metallic Half-Moon Betta (Luna), 4 Corydoras Pygmaeus, 6 Dwarf Gold Banded Barbs, 2 Panda Corydoras, 3 Otocinclus, 1 Red Shrimp.
(from his tank list)
If it is only effecting the labyrinth fish then it could be something effecting the labyrinth organ. Metafix or betta fix will effect it.

 

[Vikesfankevin]

I know not all barbs are agressive but maybe the barbs are battering the bettas.