What happened to my fish??

Question
Hi, basically I have a medium sized pond in my garden and we had 3 goldfish. Today my brother cleaned out the filter which we do once a week and then after a couple of hours one of our fish died (we think it was the female) we tried to revive her by moving her in a figure of 8 movement but there was no luck and all the scales were falling off. We also realised that none of the fish had eaten the food we had given them today. We are really unsure about what happened but we are thinking it could be constipation??? please help :(

Answer
Hi Nallini,
 I don't think constipation would do that and particularly not that quickly.  Is there any chance that some chlorine/bleach or other cleaning substance got into the pond?  

-- Ron
  rcoleman@cichlidresearch.com
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