NANFA-L-- Mystery tentatively solved

Mysteryman (
Wed, 28 Jun 2006 08:00:20 -0500

That weird mystery malady that was wiping out my Rainbow Shiners has been
narrowed down to a ciliated protozoan. These little beasties are in the habit
of attaching to the caudal fin, tearing it to shreds, and feasting on the
blood. Loss of blood is apparently the cause of death for the affected fish,
although no bleeding is visible unless the crust of parasites is removed. The
gills are strangely left alone; the parasite has a strong affinity for the
caudal fin. The other fins are also largely ignored. The white crusty
appearance is due to a congregation of thousands of the creatures piled up on
the fins & each other. Just how they swarm so suddenly in such great number
and attach to fish in such a very short time is something I haven't figured
out, but it does-in-least explain the way the fish are fine all night and only
attacked in the morning. I guess the parasites wake up-in-dawn and begin their
Antifungal & antibiotic meds seem to retard their growth & spread for a short
while, and antiparasite meds knock them down for a lot longer. I gave the fish
a massive dose ( 3X normal ) of Coppersafe, and after about 10 days with no
further outbreaks the problem seems to be solved, although the fish are
obviously unhappy about the copper. A few massive water changes might help
them through it.
Normal copper doses weren't having any useful effect. I would guess that a
strong dose of Clout or similar might also work.

I never did get around to sending any specimens to a lab, but I will. I just
used my own microscope and pored through a whole bunch of books on the
subject, finally finding one obscure reference in a very old book printed back
when people still commonly kept natives. No physical description of the
parasite in that example is given, so I don't know if that's the culprit.
Cyclochaeta is the name of it, or-in-least it was way back then, and the
symptoms described are a good match for what my poor little rainbows
I've never before heard of this Cyclochaeta, and that's odd in itself, since I
have a LOT of books on the subject of fish diseases. Oh, well; the newer books
have long had the irksome habit of leaving out good stuff from times past,

Anyway, I figured you guys would like to know about this irritating little
beastie in case you have the same symptoms in your fish someday. This
knowledge came too late to save my Rainbows, but my Flagfins are okay. Luckily
my Bluenoses were never exposed; I'm sure they wouldn't have had a chance.
By the way, the Warmouth milt has had zero effect on the bluenoses in regard
to making them spawn, although they are in full spawning condition and
courting constantly. ( Quite a sight! Who needs Bettas with this action going
on? ) I guess I'm gonna have to find a Longear.
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