My handsome little Lancelot's fins got ripped up, so I took out the plastic plants (they were very soft, and I'm still not convinced they were the culprit) and treated his 5 gal tank with tetracycline. I hate that medication, because it's turned my tank water blood red. 
Anyway, I followed the instructions carefully, and after the treatment, I thought I'd taken care of the fin rot, because his fins were growing back quite well. But... not so much anymore. The last dose was about 1.5 - 2 weeks ago, and tonight I noticed that his fins are shredded again, and there are some large holes in the fins, near the outer edge.
So, my questions are these: First, is this bacterial fin rot, or could it be a fungal infection? Second, in your experience, what is the easiest, yet most effective way to get rid of this sort of problem? In the past, tetracycline has always worked fine, but this seems to be a particularly persistant strain, and I want to avoid making my water any redder than it is now. (I just got out to the store and got some carbon for my filter. My water is currently the color of red wine, and it's hard to see a red fish in red water.)
My apologies for the length of the post. I tend to be verbose. And, thanks in advance for any help that you can offer to me!
Anyway, I followed the instructions carefully, and after the treatment, I thought I'd taken care of the fin rot, because his fins were growing back quite well. But... not so much anymore. The last dose was about 1.5 - 2 weeks ago, and tonight I noticed that his fins are shredded again, and there are some large holes in the fins, near the outer edge.So, my questions are these: First, is this bacterial fin rot, or could it be a fungal infection? Second, in your experience, what is the easiest, yet most effective way to get rid of this sort of problem? In the past, tetracycline has always worked fine, but this seems to be a particularly persistant strain, and I want to avoid making my water any redder than it is now. (I just got out to the store and got some carbon for my filter. My water is currently the color of red wine, and it's hard to see a red fish in red water.)
My apologies for the length of the post. I tend to be verbose. And, thanks in advance for any help that you can offer to me!