This script exclude Admins users from Members directory on BuddyPress.

buddypress-exclude-members.php

add_action( 'bp_legacy_theme_ajax_querystring','bprm_exclude_members',20 , 2 );
add_action( 'bp_ajax_querystring','bprm_exclude_members',20 , 2 );

function bprm_exclude_members( $qs=false, $object = false ){

  global $bp;

	//list of users to exclude
	//comma separated ids of users whom you want to exclude
	// for example '0,1,54'
	$excluded_members = join( ',', bprm_get_admin_users_ids() );

	//if the current loggedin member is in the excluded members
	//then the exclusion is ignored
	if ( bp_loggedin_user_domain() ) {
		$user_id = $bp->loggedin_user->id;
		if ( in_array( $user_id , explode( ",", $excluded_members ) ) )
			return $qs;
	}

	if( $object != 'members' )//hide for members only
		return $qs;

	$args = wp_parse_args($qs);
	
	//check if we are searching for friends list etc?, do not exclude in this case
	if(!empty($args['user_id']))
		return $qs;

	if(!empty($args['exclude']))
		$args['exclude'] = $args['exclude'].','. $excluded_members;
	else
		$args['exclude'] = $excluded_members;
		$qs = build_query($args);
	return $qs;
}
 
add_filter( 'bp_core_get_user_domain', 'bprm_core_get_user_domain' ,10 , 4 );
function bprm_core_get_user_domain($domain, $user_id, $user_nicename, $user_login){
	
	global $bp;

	//list of users to exclude
	// for example array(1,2,55)
	$excluded_members = bprm_get_admin_users_ids();

	//if the current loggedin member is in the excluded members
	//then the exclusion is ignored
	if ( is_user_logged_in() ) {
		$loggedin_user_id = $bp->loggedin_user->id;
		if ( in_array( $loggedin_user_id , $excluded_members ) )
			return $domain;
	}

	if ( in_array( $user_id , $excluded_members ) )
		return null;
}

function bprm_get_admin_users_ids(){
	$admins = get_users( array( 'role' => 'administrator' ,'fields'=>'ID') );
	return $admins;
}