I typically only use ambient, not direct, lighting in QT to reduce stress. Something like light from a nearby lamp or window.I have not seen him eat yet. I have been keeping the lights out to reduce stress. But when I introduced frozen food, he didn’t budge from his corner. Also, I meant to say the tank had been cycled for 4 weeks. Should I continue to leave the lights off? How many days without eating should i be concerned? I didn’t want to start any meds until he relaxes a bit.