Re: NANFA-L-- Rampant Cottony Fungi
Thu, 01 Dec 2005 10:22:08 -0600

Caspar wrote:
> In attempted treatment i removed the first group of infected fish
> and put
> them into water treated with a teaspoon per gallon of salt for
> several days...
> with no results. I also added a bit of rock salt to the main
> tank... but not
> much for concern of killing the plants.
> What more can i do?
> and once a fish gets this growth of cotton fungi can it be saved?

_Saprolegnia_, also called water mold, is ubiquitous in aquatic
environments, being most abundant in organically enriched situations.
The spores are tiny, resistant to most chemicals, and cannot be
eliminated from tanks while they are populated, in my experience, and
according to my references. Bleach will do a job on them in a tank,
but obviously would do a job on any occupants of a populated tank. As
soon as a tank receives water and occupants, the mold is introduced, so
far as I can tell. It is not normally a pathogen, but is
opportunistic, attacking stressed and particularly injured fish.
Better tank health and prevention of injuries to the mucous coat are
the only preventions. I have never had success trying to cure a fish
where the infection had reached a visible state, though others may know
things about treatment that I don't.


David L. McNeely, Ph.D., Professor of Biology
Langston University; P.O. Box 1500
Langston, OK 73050; email:
telephone: (405) 466-6025; fax: 405) 466-3307
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