Hey Sns, to kill 2 birds with 1 stone, when you begin flowering, you might consider taking a few of the ladies out of the LED room and flowering them under a HPS. You'll still have the results from the many plants flowering under the LEDs but you'll also have a comparison of weight from extremely similar plants flowering under 2 different scenarios. It will show how well plants respond to the light change and it will expand your experiment to cover another question many of us may be asking; is it effective to veg plants under LEDs then move them under HPS to maximize harvest?

Just some thoughts

Peace!