FC3000 Light height and dim advice

In vegging you don't need to run 100 percent. 20-40 percent will likely work depending on your distance. More light does not mean faster growth in vegging. You want the plant to have just enough that she accelerates her growth to produce leaves to catch what light there is. Too much she doesn't have to work for it or get bigger faster.

*stacking*

The FC-series are powerful. they are designed to be used full power 12 hours a day and still hit a high DLI. in vege you have 3 optioons: keep it raised like you do now, run at a lower % power or reduce hours it operates. that last one should not drop below 15hours per day or you rish a photoperiod plant going into bloom and probably safter to stick to 13 hours or less in bloom phase, though 14/10 will likely do it too. 16/8 and 13/11 are the limits for each that i use just to be extra safe. 20-24" and 65-70% 18hours/day would also work and save a few watts.. depends on context a bit which is best. ~50cm give or take. There is some genetic variation, so in the end you still have to observe resulting internode length and adjust appropriately... too much stretch and you increase light given per day. things start stcking up on top of each other and you know it needs a little less light per day.