First hydroponics rockwool grow

Hey peeps first time starting a hydro rockwool grow in a 550×330×150 slab sitting in a 45l tub with reservoir underneath. 650w led light, Strain is California dream. I’m learning on the go and researching aswell. (Not too much you will never know what to believe :joy:) I was just wondering if anyone had any tips and how often to water. Watering side of things is a automatic dripper system with 3 adjustable flow dripper stakes. Now is it bad to water while lights are off. Cheers in advanced and keep polluting the earth with natures finest chronic :v: