Best way to change lighting cycle?

[N8MAN1068]

I have a 20H tank, with a single 18" 15w GE AquaRays bulb.
I leave the lights off during the day, but they are on from 7:30pm-7am, primarily as a night light for my daughter(tank is in her room...lights/white noise helps babies sleep).

I have a new fixture+set of 130w daylight/actintic mix w/ moonlights come in friday. Now, I don't want to just blast the things on..so whats the best way to to move over to a proper day/moonlight cycle?

 

[Blown 346]

Since you want to ease into it, I would have them on for 2 hour the first day, and add 30 minutes each day after that until you reach the full lighting time.