This topic is completely personal preference. There is no hard and fast rule.
It's important however, to not overdo your lighting, but 12 hours is generally common practice.
Most will separate their actinics from their 10000k lighting to create the dawn and dusk effect. Is it neccessary, no, but it's a nice touch and some research shows it to have a positive effect on the inhabitants.
Moonlights are nice as well. They give your tank a night shimmer and if setup right, looks quite natural and pretty cool. Some say the moonlight promotes spawning etc.
The big key to remember when setting your time schedule is when is best for you!! You're the one looking at/looking after the tank, and therefore, it should revolve around your schedule. Does it make sense to come on bright and early in the morning when you are rushing to get up and out of the house.... probably not. Most like to extend their night viewing time.
I have mine set like so:
actinics on @ 10am
10000k on @ 11pm
10000k off @ 9pm
actinics off @ 10pm
HTH,
Ryan