Photoperiod / Rest Period


Lifetime Charter Member
Lifetime Member
Jul 27, 2007
New Hope, Pennsylvania
Just an observation which poses a question.

When my lights come on in the morning my plants have already completely opened up due to the rooms ambient light. Ambient light being just sunlight making its way through the blinds. Not nearly enough light to read a book or do anything productive, but enough that the room is illuminated. Same goes for when the lights go off at the end of the photoperiod, lights are on, television is on, etc, all adding ambient lighting to the room. So I've noticed that the plants never start to fully close until my routine is finishing.

The question now being how much ambient light can keep plants from fully entering a rest period? Obviously the ambient lighting we have in our homes around our tanks is more than what is in nature. Is this ambient light enough to disturb the cycle of light, enough in some instances to stress plants orcause/effect promote algea? What are the plants doing chemically and physically in the dark? Why is it during a blackout to combat algea we can see noticable growth in plants? Is this growth simply the plants searching for light or did the plants finally get a weekend off to lounge on the couch and recupperate?