Should I ramp them up slowly? Or just go to 100%?
It couldnt hurt to ramp up slowly. I have limited expertise in tuning these lights since i just started at full intensity from day one. All my frags at my LFS are grown under radions so I think they were already accustomed to very bright conditions, therefore not needing to have been slowly adjusted to high lighting. Someone else with a broader understanding of lighting can pitch in hopefully.