Ian

in the USA, the legal limit for Copper addition is 0.5 ppm with a 0..2
ppm residual level , although in Europe it is 1.0 ppm.

You are correct that above a certain limit, a copper haze may develop -
that is usually => 0.5 ppm.

Interestingly when one does a bit of research on copper limits and the
effect on humans a great deal of literature exists that stipulate we do
not have enough copper in our bodies, and that in turn gives rise to
certain disease states. A search of "Google" will provide quite a few
references. I offer this simply to suggest that there are many questions
about toxicity levels of these chemicals. One needs to make their own
decisions. At any rate a good laboratory can determine copper levels.

One problem with the addition of copper sulfate to remove hydrogen
sulfide is the subsequent precipitation of copper sulfide in the wine.
Copper sulfide (CUS)is fine black precipitant that can be problematic.
I would suggest waiting a bit to see it you have any CUS, then racking
off of that. Subsequent fining and filtration will remove the rest - or
at least most of it.

Reagents such as potassium ferrocyanide remove copper but are not
allowed in the USA. Cufex and Metafine are proprietary copper removing
agents but are no longer marketed in the USA.

Dead yeast cells are effective in removing copper, and products do exist
that do this. Their use in combination with caseinates remove copper
from wines..

Regards

Jerry


"Ian Griffith" > wrote in message
. ..
> Anyone have any experience with some of the new products available for
> hydrogen sulphide treatments (Bocksin, Kupfat, and Kupzit)? I've done
a
> light dose of copper sulphate (.25 ppm) and that has made a huge
> improvement, but I'm curious as to other options. Copper sulphate is
toxic
> in quantity, and I understand can introduce copper haze if any more is
used
> than absolutely necessary.
>
> I've heard these new products aren't quite as risky. Anyone have any
> experience?
>
>