Betta body/fin rot!!!!

In your update you seem to be really trying to help your fish but, I dont see how anyone could let a case of rot get that bad or not notice it getting that bad. If your not allready I would check your fish for illness everyday. I wish you and your fish the best of luck.
 
It'll probably take some time for those fins to grow back, considering the fact that the infection had eaten all he way into his tail meat. He has to rebuild the flesh first. Any animal's body is going to heal according to priority over appearance. So the muscle and skin and scale first, then the fins.

And don't expect them to grow back as pretty. I know when my fish lost some finnage due to me trying to mate him with a very aggressive female, some of the rays of his fins never grew back out completely, which gave his fins a crumpled look. It didn't hinder his swimming and he still had a nice veil tail, but it was never quite as lovely as it had been. But sometimes function serves better than fanciness, right? And he seems like he's gotten real sweet on you through this whole ordeal. ^__^
 
Trust me I feel terrible that things got this bad. My husband and I have six aquariums and a vivarium. I cleaned my tanks and he cleaned his. Well, when I got overwhelmed with wedding stuff and job stuff he took over cleaning my tanks. I saw that his fins weren't looking up to par before he starting the cleanings. I thought it was due to me not keeping the water as clean as I should. I figured that when he started cleaning the tanks on a regular basis that it would be ok. Well I guess not-I went to take a close look at my little aquarium and that is what I saw. I thought he would let me know if a fish was hurting etc, but I assumed wrong. That is the sob story of how poor betta got in this shape. However, he seems to be doing better and he still is a happy little betta, now with gobs of attention.
 
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