yep, that's done the trick. One final thing if I'm setting the hour to be 6, how do I know if its am or pm? or how can I set it to be 18:00 instead of 6?
That's what the high bits of the hour are for. From the datasheet, you have in the top nibble: bit 2 selects 12 or 24 hour time, bit 1 is either the am/pm indicator or the high bit of the 24 hour time.
So use (0x40 | your_time) for 24-hour, or ( ((is_am) ? 0 : 0x02) | your_time) for am/pm mode.