A good explanation of what to do can be found in Lum's book. Just
download it and search for copper. He talks about 1% copper sulfate
which is the most common one sold. I know Presque Isle sells it, I
keep it on hand; piwine/com. You should be able to find it many
places. The link:

http://home.att.net/~lumeisenman/book.doc

Joe