Agressive beta

Question
I left my fish in the care of my roommate for the weekend and when I arrived
back home he was angry and aggressive and will not eat. In fact he darts to
the top of his bowl and swims around in circles, all puffed up, then swims to
the bottom and knocks some of his rocks against the glass. The he stay at
the bottom all puffed up moving his fins rapidly.  This has been going on for
a week. I am worried because this is not his normal behavior and he is
not eating. I want to know what could be causing this or what I can do to help
him be the calm, peace, happy beta he was?

Thanks

Answer
Hi Milan,
 It could be that something happened while you were away but it also could be that it is getting warmer out.  By any chance is your betta in a tank that doesn't have a heater?  If so, the warmer weather will have made his water warmer and he could
easily be feeling the effects of that, i.e., he thinks it is spring and time to think about breeding.  Has he started making a bubble nest?

 This is just a theory but let me know about the heater.  

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>