Fin rot & Bio Wheels

Question
Hello.  I have two goldfish, and seem to be having a problem with fin-rot either recurring or not going away entirely. One goldfish has a little bit of black edging his tail-fin, which ended up getting ragged last time. I've treated with a general Fungus Cure (which worked last time) and followed the instructions on package re: water & cartridge change. Last time I also did a thorough clean of the gravel and tank. (3 months later is when the fungus showed up again, though water clarity etc was fine.) I also added new BioSpira bacteria to the new water, which has maintained water clarity before. I was wondering, though, if the reoccurence is because the BioWheel is 'infected'... or if the Fungus Cure meds might have damaged it...  Any advice or suggestions would be welcome! (Besides "why are you spending this much time, effort and money on two fish that cost you 50 cents each?", which is a friend's favorite tease. ;))  Thanks!

Answer
Well, it is very odd that the fin rot continues to come back. I would definately suspect that the biowheel was affected by the treatment, it would have been a good idea to remove that during treatment. See if you can get a new biowheel to replace the old one. Other than that, it is hard to day why exactly the fish continue to get the fungus. It is likely that while the symptoms are gone when you treat them, the actual problem, the fin rot, is just masked by the treatment. As in, sometimes when we get really bad colds we take antibiotics and after the treatment it comes back, in other words our cold has just been lessened and not cured. Basically, the treatment gave the fishes immune system alittle boost and thats why they got better but actually they are still sick. Other than this reason causing the reaccurance, I would only next suspect extra stress. Have you added new fish or done anything to the tank that might have added extra stress to the fish? If not, I highly recommend getting a very strong fungal treatment and re-treating, even if the fish have no symptoms, to be sure they are cured. I recommend getting a fungal treatment by the brand Mardel, you can get this at your local petstore and it is a strong yet safe treatment to use. Now, of course this recommendation is optional and you can wait until another illness presents before you re-treat. The ideas I give you are simple what I would do but again it is not always best for everyone. If you re-treat be sure to remove the filter and the biowheel, try to replace the biowheel with a new one. Follow the dosing and water change requirements as well. I hope this helps. In reference to the tease from your friend, yes you did only pay 50 cents but the fish is still a living thing and you have developed attachments to it. No one, in thier right mind, wants to see any living thing suffer. Treating them was only the humane thing to do. Just think, you rescued two fish that would have actually gone to be food for something, the cheap fish often become food for other carnivore fish or reptiles. Yes, it is ironic that you spent 50 cents and have to pay more to treat them but it is wonderful to appreciate their beauty and do everything you can to make sure they have normal, happy lives :-D Let me know if you need anything else.