Betta sore on flank

Question
Hi Ron, I'm hoping you can help.  My beloved Betta who's about a year and a half old had a tiny whitish area on his flank about a week ago that looked like he may have scraped a fin on something (though I can't imagine on what).  He's in a 2 and a half gallon tank with filter and has been doing so well.  He's eating normally, swimming normally and overall seems fine.  Unfortunately, the spot has now gotten a little bigger and it almost looks now like it's a bit open, like a sore rather than just a tiny scrape.  I can't make out from all the conflicting info on the internet what this is likely to be and I'm afraid to treat him with an incorrect medication.  I'm hoping that since his behavior is otherwise normal that this can be arrested before he gets worse.  Any suggestions you may have would be appreciated.  I love him so much and I'm terrified that I might do more harm than good if I try to treat this on my own.  

Answer
Hi Heather,
  Hmmm... I assume that there is nobody else in the tank with him so it isn't a bite... ?

  You are right to be cautious about treating him.  In a 2-1/2 gallon tank, there isn't a lot of room for error if you overdose him with medication.  It is possible that he did bash into something and is losing a few scales. If that was it, they will grow back (and likely in a matter of weeks or so).  If however, the wound keeps getting larger, that is bad news. At that point, I would treat him with a dose of something like Paragon II which attempts to control fungal infections which might attack such a wound.  

  In the meantime, be sure that his water is in tip-top shape and don't let any uneaten food accumulate in the tank that might aggravate the situation.  

-- Ron
  rcoleman@cichlidresearch.com
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