I'm sure its a MH for veg and sodium vapour for bloom. The sodium vapour is closer to the red end of the spectrum. I'm sure by adding an extra 400w to the 600w you will get better results. You might need to think about some extra ventilation as those 1000w bulbs are hot. 1,500 degrees+ kinda hot.

I grow with LED primarily but I also use 4x20w CFL just to create some heat in the tent. LED runs totally cool.

Check out my grow here if you have time. I'll never go bulb and ballast again.

LED Logger