BuddyPress.org

Create a file called bp-custom.php – it will go in your plugins directory.

Put this code in it:

function visitor_intercept(){
global $bp_unfiltered_uri;

if ( !is_user_logged_in() ) {
if ( ($bp_unfiltered_uri[0] == BP_MEMBERS_SLUG) || ($bp_unfiltered_uri[0] == BP_ACTIVITY_SLUG) ) {
bp_core_redirect( get_option('siteurl')."/some-page" );
}
}
}
add_action( 'wp', 'visitor_intercept', 3 );

Change “same-page” to where ever you want to send them or remove to send them to front page.
Note: this may not work if you are using BP 1.3