a fat beta

Question
I got a red beta almost six months ago and last month I noticed a lump on him. I thought I was over feeding him so I fasted him and then changed his diet to add variety. Now I feed him two small meals a day and once a week I don't feed him at all. Since then he has gotten much bigger. It looks as if he has a small marble in him. I have gone through a whole list of possible problems and haven't found one that describes my fish's symptoms. He still acts normal, no change in anyway, just appearance. What is wrong with my fish and should I put him down if he doesn't get better soon? Your help is much apprieciated. Thank you

Answer
Hi Megan,
 It sounds like he might have some sort of tumor.  Would I "put him down"?  Absolutely not.  If he acts normal, I would just keep doing what you are doing.  

-- Ron
  rcoleman@cichlidresearch.com
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