Display clock each 10 minutes x times forward in PHP

Here is a simple code PHP snippet to display the clock each 10 minutes x times in the format of:

php5 test.php
20:40
20:50
21:00
21:10
21:20
21:30
21:40

Etc.

<?php

$j = 0;
for($i=0;$i<10;$i+=1) {
        $j += (10*60);
        $hour = date("H", (time()+$j));
        $min  = ceil((date("i", (time()+$j))/10))*10;
        if($min > 50) {
                $min = "00";
                $hour++;
        }
        echo $hour.":".$min."\n";
}

?>