Hi,

You can use dual ballast 400w for your grow if you plan on growing on batch at a time. Note that you will need proper ventilation at around 150cfm - 250 cfm(some blowers between 150cfm - 250 cfm wich fits the a/c flange on the hood are great, there are some good one on eBay for around 50$) for your 400w lamp as it will produce heat in the cabinet and you need air circulation as well inside.

Btw, air coming through the blower exhaust must eject outside the cabinet to prevent re-heating the cabinet.

Hope this helps you a bit


Happy Growing!