I have seen this problem with many species of rainbowfishes that have been
bred over a lengthy period of line breeding. Also missing or deformed gill
plates are other problems that appear regularly.
If this is the first time this has happened to your parkinsoni I suggest you
destroy all the young fish and just breed them again as you may find that
the problem won't repeat itself particularly if you are breeding with a
group rather than just pair breeding. However, if successive generations
show the same problem it is time to get new breeding stock. Often you only
need one new fish to breed to your existing stock to start over.
I think it is best to breed rainbowfishes in groups rather than using only
pairs as this problem doesn't turn up very often.
Adrian Tappin.
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Adrian R. Tappin
atappin at ecn.net.au
http://www.ecn.net.au/~atappin/home.htm
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