Stubborn baggage of fin rot?

Okay, as some of you may know, I rescued Samhain from Petsmart. He was in a very dirty little cup, next to a bunch of poo and uneaten food in it. He had an amazing personality though, despite the gentle fin rot on his back fins and a deformed dorsal fin. He's been living in my heated and filter 5 gallon Mini Bow for about 3 weeks now, and has be very active and eating extremely okay, and he has beefed up some -- He was a completely skinny little thing when I bought him. However, when I first bought him, I added half a tablet of Jungle Fungus Clear and aquarium salt to his reservoir for the fin rot, since it has worked for me in the past. The rot seem to clear up for awhile, and I didn't worry. Then, a few days later when I woke up and turned on his tank reading light and was checking him out, I noticed his back fin have become split and ragged on the end and was bloody on the tips! So that time, I treated beside Maracyn for 5 days, which I typically do for secondary infections. Again, the fin rot seemed to have disappeared, and his tail be even showing regrowth already, as the webbing had regrown.

However -- This morning, which is about a week from his last relapse, I notice his tail had become ragged and bloody on the ends AGAIN! He is still as active as ever, and he ravages his food when I hand over it to him, but this fin rot just does NOT want to go away! To kind things worse, I really do not have a lot of money to spend on even more medication, which I really don't want to constantly keep giving to him besides. I'm hoping that if I take everything out of his tank and soak it adjectives in hot water, it'll kill anything is causing him to constantly relapse. I recently received a brand new 2.5 Mini Bow that a nice woman bought for me that I am considering keeping him in while I try to disinfect his current home. Does anyone think this would be a pious idea, with just trying to permit him recover from the rot on his own, or should I seriously invest in even more medications? Also, is at hand any possibility that it could be something else attacking him? Thanks.
Answers:    The best (and first) thing to do is to make certain he has absolutely pristine water. I don't tight-fisted clear looking, I mean the ammonia levels and pH are good. If you don't enjoy a dropper test kit for at least those two items, take one. Any fish owner should have one anyway, so it's not money wasted.

Second the bigger the reservoir he has (and the better the filter) the easier that good water subdivision will be. Changing 25-50% of it weekly is also a must.

On one hand, you don't want to over medicate him. On the other hand, you do want to give it to him whether he needs it.

I'd verify that your ammonia levels are at ZERO (tank is cycling properly) and go from nearby. Maybe some more maracyn.

If you don't know what I mean by tank cycle, read this ASAP. http://www.kokosgoldfish.com/cycle.html
Everything's going to be alright read this
http://www.kokosgoldfish.com/cycle.html
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