Bettas dying from medications???

[EBoxell9584]

I had 5 male bettas all for about 4 or 5 months (each in his own tank with mollies or swords) and they were doing fine then I had a problem with molly shimmies so I used molly bright in all my tanks to cure the mollies. Well, the mollies don't shimmy anymore but 3 of the 5 bettas died each having the same symptoms and dying witihn an hour of each other. Their fins began to just fall apart scales flaked off. The fish just sort of hung out at the bottom of the tank. After the first fish died we noticed that they were all like that so we put them in breeders in our sick tanks and quarantine tanks. They still died....anyone know if molly bright kills bettas? how about Mela fix? and what about quick cure? these are all medications that we sometimes have to use and i dont want to lose over half my bettas again!:confused:

[OrionGirl]

I couldn't locate anything that lists the ingredients, but from most recomended uses, it sounds like Molly Bright may contain something that changes the pH or hardness of the water. A sudden shift could hurt a betta--but this is speculative on my part. From the descriptions and causes of shimmies, I would guess that you have fairly soft water. Mollies do better in hard water, while bettas prefer soft water. This may cause problems when the 2 are mixed.

[yashinfan]

Melafix would not kill your betta.

[EBoxell9584]

we have fairly hard water and the bettas, in the past, did just fine in it. we are down to only 2 bettas now ):

[OrionGirl]

I wasn't suggesting that the hard water killed the bettas, but rather the sudden shift in the water chemistry resulting from the Molly Bright treatment. If your water is hard already, then the diagnose of shimmy is suspect--it's normally the result of these fish being in soft, low pH water.