what in the WORLD is going on!?

[justme9984]

I'm completely stumped and frustrated. I have a "female" guppy tank, with about 10 female guppies and 3 platys I have a breeder box with some fry in it as well. (Its a 29 gallon, completely cycled, been running for about 8 months. I made a stupid mistake (I ordered some live plants, and the person sent me some "free fish" (Two zebra danios) I had nowhere to put them so I stupidly put them in that tank. Shortly after, I noticed some ich symptoms in one of the danios, then ich symptoms in some of the other fish. I started treating with maracide. (shortly before this I treated the whole tank with maracin 2 because of suspected mouth fungus. That all went away, after treating with maracide, 2 fish died (including the one danio). The ich seemed to have gone away, but no one was really acting right. Well in the last week, most of the fish have developed "ich" symptoms. Tried quick cure, its not touching it. Now their fins and tails are being eaten away and they are still covered in "white" (around their fins and tails, not necessarily body) I'm assuming it is not even ich anymore. But I have no idea what it is! Water parameters are good, I'm running out of options. Any ideas??

[madagascariensis]

The ich is, of course, from the Unquarantined danios. The ensuing problems sound like fin rot, and here's the explanation i believe in: most fish medications damage the bacterial filter to some degree. After treating you have killed off a lot of your bacteria resulting in sudden poor water quality. I'd start doing large daily water changes for a week or two to let your bacteria colony recover.

[Tiari]

+1 to the above. Maracyn 2 will KILL your cycled beneficial bacteria. It may have destroyed some, or all of it, so you are likely dealing with cycling problems unaware. Though your parameters are "fine", make sure you check and test daily for fluctuations and swings. There should be zero ammonia, and zero nitrite.

[justme9984]

Thank you kindly for the replies. So are this point you are both suggesting keeping on top of water quality (daily water changes) and no medication to help the current fin/tail rot and perhaps some lingering ich?

[madagascariensis]

I think that the reason that maracyn isn't doing in the ich is because it is an antibiotic, not an antiparasite.

[justme9984]

I started Maracyn 2 quite a while ago. Put back carbon... then about a week later is when I started to see the ich, so I tried Maracide. Didn't TOUCH it. Almost 100% water change then I tried quick cure. still not touching the "ich" if thats even what it is.