That's interesting, if I understand correctly, high K light (actinic) mostly produce blue light with wavelength roughly between 400-500 nm. The chrolophyll is most effective in absorbing light wavelength of 430nm and 660nm. So theoretically speaking grow light (4000K), Daylight (5000K) and Super Daylight (6500K) fluoresent lamp should be more effective since they produce full spectrum light.
In nature high K environment is mostly found underwater >15 feet deep.... Hence high K light shouldn't be more effective compared to those full spectrum light when growing terrestrial plants... right??
I used to be nuts with planted tanks....
