No problem. Set Timer 2 under Timers exactly the same except starting 30 minutes later. Set PC#4 for Timer 2 and PC#1 for Timer 1. Make sure to only set each one for the one timer though. It prompts you for a second timer, and you need to leave that 0. You didn't mention that you set the "Off Duration", but don't forget that too. Also, you mention picking 01 and 02 on the PC4 in the Multi timer. I'm assuming you're talking about under "Function". Mine shows "Timer A" with a flashing "1" for me to pick Multi Timer 1, then prompts me for "Timer B" with a flashing "0" that I leave 0. I don't see 01 or 02 in any of the screens for my system, just single digit numbers. Have you downloaded the latest firmware from Digital Aquatics? They've got a pretty recent download available, and that might be why I'm seeing something different.