Male Beta has a swollen belly

Question
From reading through some of the previous questions, I gather that our Beta has either constipation or dropsy.  How do I tell the difference.

His belly is bulging out on the bottom behind his gills and stops before his back tail.  His color is fine and he doesn't have the "pine cone" scales sticking out.  He is still making his bubble nests.

We have been changing out 100% of his water every 2 weeks - per our pet stores instructions.  From reading today, I gather we should change out 25% every week?  We also don't keep his tank at 75-80 degrees.  His tank is whatever our house temp. is.

Any help would be appreciated.  I could send you a picture if you'd like.

Thank you,
Michelle

Answer
Hi Michelle,
 I think you should be changing water more frequently and you should purchase a heater to keep his temperature a little more stable.  

 His bulging belly could simply be that you are feeding him too much ... is that a possibility?  

-- Ron
  rcoleman@cichlidresearch.com
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