White Balls forming on my fish

Question
I have a fairly new tank and my angel fish just died this morning
and Istarted noticing small white balls forming on the rest of my
fish in my fresh water tank.  They are all tropical fish.  I got the
water tested yesterday and the people at petsmart said it was fine.  
What is it?  What can I do?  Are the fish going to be okay?  Help!  

Answer
Hi Elizabeth,
 When you say "white balls", do you mean tiny little white balls that look a bit like the fish was dusted lightly in icing sugar?   If so, that is a disease called ick.  Ick is deadly but can be treated if you act very quickly.  There are many products available: I use one called Rid-Ick but there are lots of others.  

-- Ron
  rcoleman@cichlidresearch.com
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