This post by Ben (Pooldoc), while a response to a question about the Nature2 system, has some good information on using copper in pool water as an algaecide more generally (it even talks about intentionally staining white plaster pools). From his post, I would gather that unless you're willing to stain the pool (and the hair and fingernails that get in it), the amount of copper you'll put in the water won't be of any help in fighting algae.

Your problem is probably a result of insufficient or inconsistent chlorination. Post your numbers (as Aylad said) and the folks here will be very happy to help you with that.