>Denise wisely cautioned against the use of copper because of its toxicity
>and the difficulty predicting how safe it will be in each situation.In my
>experience it is also a problem knowing which fish will react badly to it -
> at the same dose different species will have problems. For example I had
>some velvet (Oodinium) which I treated apparently successfully with a
>Copper-based "cure" then removed the M. duboulayi and cleaned the tank did
>a total water change but felt that the cleaned gravel should be OK and
>several days later put some Poppondettas in and that evening was horrified
>to see them diong a "whirling disease" impersonation which accounted for
>half of them. My feeling is - don't use copper unless there isn't anything
>else !
I had a bad experience with copper some years ago when I treated a tank for
velvet and did exactly what Bruce did (completely breakdown and reset-up).
When I put the fish back into the tank they rolled over within hours. I
stripped that tank down 2 more times with the same result and on the last
effort used one of those absorbent products (can remember the name) anyway
it turned blue. In the end I had to replace all the gravel with new material
as it was obliviously releasing copper back into the system all the time.
The only problem is you sometimes come across what I describe as "stubborn"
velvet that doesn't seems to respond to formalin, malachite green treatments
(either alone or in combination) and copper seems to be the only thing that
works. Chelated copper products don't work on it either.
Adrian.
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Adrian R. Tappin
"Home of the Rainbowfish"
http://www.ecn.net.au/~atappin/home.htm
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