I definitely misread that as to 20 sec and for a moment I thought, "so... what's the problem?"
On topic, once it is booted up, is the performance affected at all? Have you encountered any sort of errors or kernel panics? I'm not sure you need to do this anymore, but in Sys Prefs, just set your drive as the boot drive just in case. I'm assuming you have an SSD given the 30s boot, but we need some more information before we can help you diagnose the problem.