Just scale your op to 6kw.
https://www.rollitup.org/hydroponics-aeroponics/6592-get-harvest-every-2-weeks.html
It's all explained very clearly and simply. He's running 2kw (plus another 400w HPS for his 5 moms) - and getting around 20 oz every 2 weeks.
With 6kw, expect around 60 when you get it...
Flood/Drain system ala Al B Fuct.
Also, check out this clean 6kw setup.
http://www.icmag.com/ic/showthread.php?t=108395
Either way, I think SOG's in your future... especially if you intend to leave it unattended for a few days.