Preventing bacterial problems

[confusion]

I debated whether this should go here or in the sick fish forum... Anyhow, I have lost all of my swordtails to bacterial infections - 5 of them. I have 7 zebra danio, 2 plecos and 19 baby swordtails that came before one of the mommas died.

My question is this: what can I do to prevent new fish I get from meeting the same fate as these? One thing to note was that my tanks were not cycled at the time I originally got them, but they are well in the process now (thanks to bio spira). Would the stress of an uncycled tank cause that, did the fish come already infected, or do I have poor filtration or some other problem that I can fix?

My plecos, danios and baby swordtails are all doing great, by the way.

In my 55G, I have a pengiun 350 filter, 7 zebra danios, and 19 baby swordtails. Originally, I put my adult swordtails in this tank, and the got sick almost as soon as I put them in (I did acclimate them over about 30 minutes). When they died, I replaced them. The new ones got sick, so I bought the 10G tank as a quarentine and tried to rehab them. They also died. I changed my water in the 10G, cleaned the filter, etc, and tried again with new fish, and those died. All from bacterial infections (columaris, I think is how its spelled), though one appeared to have dropsy - visible veins, etc.

Any ideas, suggestions or tips would be appreciated.

Thanks

 

[BillD]

While this may not be the answer, the fact that the new fish died in the QT, would lead me to believe it was still infected after you cleaned it. I use bleach to steralize any tank before reuse, whether there was disease in it or not. This means bleaching the filter and anything else in the tank. Small tanks, I often runthrough the dishwasher, using dishwasher detergrnt. A 10 gal tank will fit in the dishwasher. Especially good for show tanks and drum bowls.