Plants do need a rest period. (Dark time) all living things do. Nighttime is when plants grow. They work during the day and reap the rewards at night. Leaving the lights on 24 hrs a day will not allow a plant to build its cells up. But they would quit photosynthesizing after a day period (6-14 hrs depending on species). How would you function with light 24 hrs a day. Just ask a third shift worker how it feels when they make that change
Some even put sheets up over curtains to remove all light from the room while they sleep.
__________________
For in much wisdom [is] much grief: and he that increaseth knowledge increaseth sorrow.
Member of the AGA (Aquatic Gardner's Association)
Member of the IBC (International Betta Congress)