lesions on betta fish

Question
MY beta has what looks to me like white lesions. I have just one in a large fish bowl. I use water from tap but let it set for a couple of hours before I clean bowl. i also treat the water. I have also found that she has stopped eating. can you please help me?

Answer
Hi Jeannie,
  First, it is important to treat the water before you put it in the bowl. It is also important to change the water frequently, at least once a week.  Also, do not change all the water. Change only 50% at most at one time. Finally, keep in mind that bettas are tropical fish and need water up near 80oF.  At lower temperatures, they basically "shut down" and typically sit on the bottom and do not eat.  The bottom line is that a betta is much happier in a typical aquarium with a heater and filter, even a small one like a 5 gallon tank, than it is in a bowl.

-- Ron C.
  rcoleman@cichlidresearch.com
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