Aside from drooping, does anyone know of any indications of under or over watering?

Every morning they look great, in the afternoon they look great also. I'm usually at work when it happens, so I'm guessing that around 10 or 11pm, they droop. Then they look good again in the morning, after six hours of dark. Some more than others. The 2 AK-48 plants look mostly unaffected. The others look like hell. I started at 4x 15min per day; at lights on, every six hours. Tried every four hours. Should I go with more, or less? Should I increase or decrease the interval, or the duration...both I'm sure.

This definitely happens during the warmest 8 hours of the day. Since I've messed with the intake and exhaust a little bit, the temp stays between 73 and 78.8 with the lights on, gets down to 63 with the lights off.

Any thoughts would be appreciated.