Network VS Site actiation

I want to know, I am doing a multi site However I would ONLy like to have soe plugins for the Main site and for my members sites, hae other plugins atiated. How would I do this My main site is http://www.diyodfy.com. Plugins like chat, appointments, I do not want on the main site but on the other sites. How do I only let the subsites hae them?