"Derek Broughton" wrote
OTOH, I doubt that the stuff put into a hot tub over the years is likely
to be harmful to the fish.

C'est vrai (two can play at this game!). I would be slightly concerned
about gel coats for boats. I imagine its possible to get them containing
anti-fouling agents - which are typically toxic to invertebrates. I'd
want
to avoid those.


C'est vrai! You definitely don't want to use any gel coating with
anti-fouling additives. However, they are fairly rare, since the
anti-fouling materials are usually in the bottom paint and not in the
fiberglass gel. And you also want to let the stuff completely cure ("dry",
so to speak) because it gives off some pretty nasty vapors until it is
cured.

Michael
New Orleans, Louisiana USA
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