bumping up hour by one

I'm having some problem with some code where I'm trying to round the hour up to the next hour if the minutes are between 53 and 59. Here's the important part of the code so you can see what I'm trying to do. $display_time = date("H:i"); // round time $display_timex = explode (":",$display_time) ; and then... elseif (($display_timex[1] >= 53) && ($display_timex[1] <= 59)) { $display_timex[0]++; $insert_time = $display_timex[0] . ":00"; } I've also tried ... elseif (($display_timex[1] >= 53) && ($display_timex[1] <= 59)) { $display_timex[0] = $display_timex[0] + 1; $insert_time = $display_timex[0] . ":00"; } Is it because display_timex[0] is not a number???? Thanks, Tom