No, it's almost certainly fin rot or fungus... what we're saying is that the fin rot isn't the problem
per se, but a symptom.
Treating fin rot is easy. Go to the aquarium store, buy some fin rot remedy, and provided the damage isn't too far gone, the fish will be fine.
But treating the fin rot is skirting around the problem. At its most simple, the problem is this: in a small tank and in small numbers, black widow tetras tend to attack one another. There are two cures.
- Double the number of black widows, which may mean moving them to a larger tank.
- Return the black widows, and pass the problem on to someone else.
There really isn't anything much else you can do. If you choose to leave the fish in the tank as they are, and then add some other community fish, then the problem won't go away and could become worse. At best, the black widows will merely attack one another constantly, and you'll need to continunally add fin rot remedy. Things might settle for a while, but at some point one or other fish will decide to try and climb up the pecking order, and before you know it, the problem will be back. At worse, the black widows will vent some of this behaviour on the other fish, particularly slow moving things like livebearers, angels, Siamese fighters, gobies, and so on.
I'm sorry to make this all sound so gloomy. For what it's worth, you're not the first person to have been suckered into buying these fish. The list of fish that really aren't peaceful community fish despite being sold as such (unless you
reallyknow what you're doing) is long: blue gouramis, yellow gouramis, serpae tetras, most
Botias, convict cichlids, red-tailed black sharks, etc., etc...
Cheers,
Neale
So what your saying is that it most likley isn't fin rot but the hierarchy is being re-established thats why it seems like everyones fins are getting shorter? Is thier anything I can do to prevent infection like fin rot or something from building up on their fins? I know I can't use salt because of the pleco but is their anything else I can do?