CHIRP -- Last time, I left the lights off (save for their chili pepper lights, which is their nightlight). I would pop in mid-night to give some fresh egg food and I'd leave it on for 15-20 min while they ate and fed baby.
Then, turned it back off til morning.
(I'd had issues with the parents not feeding, so I was overly cautious.)
This time, I have a sick bird in a sick cage beside my main cage and she has a heat lamp on 24/7, so it lights up the room a fair amount.
I've noticed they're much more active and they feed the babies more frequently at night.
These babies grew and developed much faster than Squeepers (same parents.) I don't know if it's just genetics or whether the extra night feedings had an impact.
But it definitely made them feed more.
Though on the flip side, it bothers me that they don't seem to be getting a good night's sleep. But there's nothing I can do. I can't turn off the heat lamp, so.