Growth On Betta?! Please Answer!

[KruseZoo]

I came home today and saw this on my betta! I am ashamed to saw that I have been neglecting his tank for the past couple weeks. I havnt been doing enough water changes or gravel vacuuming. If this is the cause of whatever this is I will feel terrible. I have no idea how old he is. I got him from the LFS and 2 years ago. He lives alone in a 10 gallon with many trumpet snails. Any ideas what this is or how to cure it? Thanks!
 
pictures:
 
  http/www.flickr.com/photos/90428002@N03/

 

[FishHelper101]

The first thing that came to mind when I saw this is that it might be septicemia. It looks like an open wound that melafix might help but I've heard a lot of opinions on melafix for betta fish. This might be an odd question but is he pooping normally? It could be a bacterial infection but living on decor in the tank. I'd try maracyn with a dosage of 2 between 2-5 days. This can also help the appetite stay normal if it seems to drop.