Whats goiong on with our Beta Fish

Question
Well it isn't always brown, if he does have a parasite is there anything that we can do to treat it and get rid of it. Do you know what causes them to get the parasites and how can we prevent them from future occurrences
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-----Question-----
My Husband and I got a beta fish (Puff) about 3 months ago and everything was going great he seemed happy and enjoying life. A couple of weeks ago we noticed that he stopped eating and then we notice this Long white string type thing coming out of his underside. It remained there for a  couple of days and then we noticed it feel off. Then he started eating again and then the same thing happed about four days later. I think that it is his fecal matter because now when it happens it is a brown color and was wondering if you have any suggestions on how to cure this or what exactly is wrong with him. Puff has got the best personality I have ever seen in a fish and I am worried that something serious might be wrong with him.

Thank You for your time,

Veronica
-----Answer-----
Hi Veronica,
 Yes the is fecal matter and if it is brown, that is great. White is bad and usually indicates intestinal parasites; however, because you say it is now brown, I would consider that good news.

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


Answer
Hi Veronica,
  He likely had a certain level of parasites when you got him -- most do.  The best thing you can do is treat him well and keep him healthy and he will fight off the parasites on his own.  There are medicines that claim to do good things, I haven't had particularly good experiences with them.  

  Regular partial water changes (20% a week, every week) are your best strategy.  

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