Waterfarm complete system questions

Hey guys, I bought this online today http://www.4hydro.com/hydroponics/cocogrower.asp and I was wondering how often I run the pump? Is it a few times a light cycle? Or is it constant? Thanks for the help...+rep for those who can lend a hand!
~Jonboy

anyone? I read that there are people who run the pump continuously while the lights are on, and shut off when lights are off....then there are people that run it 24/7

anyone?