Hey,
I went into my LFS and asked for 'lead' to weigh my plants down, the guy gave me a strip of something which I took to be lead, but thinking about it now, it probably wasn't. It was properly packaged with pictures of little fishies on the box (or something similar), so I'm sure it's fine for fish. That, and of course the fact that it's been in there for about 3 years with no apparant ill-effects...
Oh, and very good Vectrum, very good indeed.