I'd get a red light bulb you can buy them just about any hardware store, that is why they are staying up all night. if you can't get one in 75-100 then go for 60 as long as they aren't in a draft they will be fine. I bought my red light bulb at Lowes.
Something else that hasn't been mentioned is when you start introducing other food besides starter, they will need grit, since they don't have teeth to chew with they need the grit to grind up the lettuce etc that they are eating. and as for olives, thats alot of sodium I don't think I'd give...