a cardboard box.??? please don't put a 400w HID in a cardboard box setup. hehe. I hope im wrong. and its not a cardboard box. but the pics, I see card board walls

I mean if you look at your plants. they look just fine under the 4 cfl's you had.. they are just a little nute burned on the tips.
they sure got pretty big for just 4 bulbs. let that speak for its self