phpredis zRange return - php

Question

I'm getting a http 500 error when trying to post to this leaderboard index:
<?php
$reference = "sorted";
$printboard = "leaderboard";
$my_win = 0;
$my_check = 0;
//get the name or member or element of the lowest score
$my_check = $redis->zRange($reference, 0, 0);
//I have the lowest ranking member now get that members score to check against
$my_win = $redis->zScore($reference, $my_check[0]);
//$wins is what I'm posting to this index
if ($my_win < $wins) {
$redis->zDelete($reference, $my_check);//I beat the lowest ranking user so take his spot
//update the new score and push the new user to the print list
$redis->zAdd($reference,$wins, $name);
//if im adding someone new I need to remove someone
//if this is running I want to strip the list of it's 99th user so don't use 1188 use 1176
$redis->listTrim($printboard, 0, 1176);
//then rpush the new player to have made the list
$redis->rpush($printboard,$name,$avatar,$wins,$losses,$ties,$fave,$meter,$game1,$game2,$game3,$game4,$game5);
}
?>
Is my use of zRange correct?
$my_check = $redis->zRange($reference, 0, 0);
And then checking the first array spot?
$my_win = $redis->zScore($reference, $my_check[0]);
I think this may be my issue am I using the return of $my_check incorrectly?
Also, with Redis do you ever need to initialize anything?
I frequently go over the phpredis GitHub manual and the redis website itself and didn't note any details about what happens if you use zRange on an empty sorted set.