top of medium looks dry...
That may be wilt, not overwatering, since it's also been a while since the act of watering.
are you watering until there is some run off? if not, you may not be saturating the soil/coco completely. If you are familiar with dry and wet weight, you can easily eliminate this as a possibility and ignore me.
watering when lights come on is definitely the better way to go. A guideline.. e.g. if oyu are leaving for the weekend, it's better to water at night before you go than not at all :) in general, you want to provide available nutrients when they will be most in demand.
Okay, i looked at diary, and you need to water more. That's all.. don't fertilize the first couple times, just in case evaporation caused some buildup... any hint of yellow and go back to normal schedule, if it was working well preivously.
wait for 1/2-1" to dry on top.. water throroughly again (or with fertilizer as you do normally).. feel weight when it is wet... feel when dry... can help when soemthing is deceiving your inside pot where you can't see.