BuddyPress on Multisite

Hi,

I am working on setting up a multisite and we want BuddyPress only be active on the main site, not any sub-domain sites. I have added plugins, but when I go to the main site I am not able to activate BuddyPress only there, I only see the option on the network admin. Is there a way around this or something I missed? All I have done is setup the multisite platform and added plugins, haven't activated any yet.

Thanks!

Dana