Library groups issue

We have a requirement from a user, which is for a simple SharePoint site with 7 libraries.  As part of this, as a best practice, we went ahead and created the top site and created the 7 libraries.  For the permissions part, we have 3 groups at the site level now.. site owners, site members, and site visitors....

For the 7 libraries, can we implement similar groups - library 1 owners, library 1 members, library 1 visitors?  If that is the case, the list would be huge and in the near future if there is any subsites/libraries in this site, it may become very difficult to manage the sharepoint groups in the site.  Could somebody please help me on how to manage the permissions here?

Shonilchi..