Actually , its the other way around. I used to just veg with my 600w MH. When I added the HPS spectrum, the plants just sucked it up and I couldnt believe the way they took off all thick and full. They actually tripled in vigor and fullness of growth. Thats 300% increase. Im expecting a bumper harvest from this batch of ladies. There are multiple strains with different finishing times so Ill be perpetually harvesting them over a 3 week period so that takes a little load off the trimming time. Once they were ready to flower, I changed out the 1 MH bulb for an HPS bulb so my ladies have been under 2 600w HPS lamps with 6" duct work taking out all the heat since they were flipped.
I got to say that I LOVE the way they came out vegging them under a 600w MH and an 600w HPS. I couldnt have asked for any better plants. It brought them too there full potential.
OH. Good Morning to you too Calidadd.