bp_core_remove_subnav_item Function

Hello all

I am totally new to Buddypress here.. and am tailoring BP Fun a little. As such I need some control over the itesm that are appearing in the user subnav in the profile section

Currently, in an attempt to keep things simple..I am trying to remove Just the activity link from a BP Fun profile pages using bp_core_remove_subnav_item()

I have added the following to my bp_custom.php file..

function my_remove_activities_from_nav() {
global $bp;
bp_core_remove_subnav_item( $bp->profile->id, 'activity' );
}
add_action( 'xprofile_setup_nav', 'my_remove_activities_from_nav' );

I understand the bp_core_remove_subnav_item function needs parent_id and slug.. I am making some guesses here on how to get the parent id ($bp->profile->id) and I am assuming the slug to be "activity" (lowercase).. Yet i cannot get this item to actually be removed

I am a little unsure about actions and how the function precisely. Do I have to put "<?php do_action( 'my_remove_activities_from_nav' ) ?>" in my mytheme/member/single/home.php file?

Am i referencing the proper parent value - $bp->profile->id?