Hi Samanthrax: Unfortunately there's nothing proven "as a matter of hard science" in the harmfulness of this widely used preservative, as far as fish-we-keep-in-tanks/ponds.
That same info is included in a great forum I'm part of: oscarfishlover.
http://www.oscarfishlover.com/index....e-Worried.html
I have been searching for info on it too, but so far, the reports of fish having long and happy lives whose primary diet included or even was limited to fish food with this preservative, speaks otherwise. This could be "a-political-position", in other words, a judgment, not a scientific fact, like claiming aspartame as being a health threat for human use.
I wonder how so many fish food manufacturers consider/keep using a preservative that causes mortality in fish, this companies, in the XXI Century have shown to be quite client oriented, the fact they make good money has nothing to do with being or not responsible in what they serve.
To name only two: New Life Spectrum & Tetra. I recently found, in Santo Domingo, where options are quite limited, a brand of fish food without it: Aqueon. I might give it a try, since I like to provide variety to my fishes.
I am a man of science, so I figure I will wait for real hard evidence to show. Double blind controlled trials are required for this, case reports do not suffice.
As for fish food concerns I wish I could have access to those with fish fillet as ingredient instead of fish meal.
Pepe
Santo Domingo
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