Ive also read that higher energy infrared and ultraviolet can increase resin production because of the sunscreen effect, which doesnt neccessarily increase potency. I tried feeding my last batch 3 t5 blacklights....some of the plants turned purple within a week, which may also be attributed to the flora nova 2 part series of nutes , which i read may cause plants to turn purple. The other plants did NOT like the UV light, and they burned from it, with little polkadot burns all over the parts up to 1 foot of the lights. The current batch has been eating ultraviolet blacklight since they developed a real serrated leaf right after cotyledons (baby leaves without seration). They are growing robustly with no sign of adverse effects, just started week 1 of flower. These are the purps from last batch ......the big purple one is from outdoors.