I have seen this a number of times, but only in Goyder R. Rainbowfish. As
"Philter4" replied it is believed to be a deficiency of iodine which causes
a swelling of the Thyroid. If you actually look under the gill cover, you
will see a swelling which can become quite large in specimens that have had
the problem for a long time. Infected fish seem to survive for a long time
with this problem but eventually it gets them in the end?
The unusual thing is that not all fish are affected. One would think that if
the diet is deficient in iodine, then all the fish would be affected, but
that's not the case?
I have tried the Potassium iodide and iodine solution as recommended by
Dieter Untergasser in his fish disease book but never got any reasonable
results?
Adrian.
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Adrian R. Tappin
Home of the Rainbowfish
http://www.ecn.net.au/~atappin/home.htm
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