1.Have a very close look at their body and fins and compare them to the
other unaffected fish and see if they have white spot or velvet? They are
very susceptible to a fine velvet which is even smaller than the normal
velvet. Very difficult to see unless you have very good eye sight. Generally
you only notice it when they show similar symptoms to that you are describing.
2.Check your temperature and see if it has dropped significantly?
Adrian.
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Adrian R. Tappin
"Home of the Rainbowfish"
http://www.ecn.net.au/~atappin/home.htm
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