Baby Giant Day Gecko problems?

I have a two Minh old giant day gecko. He was in a 29 gallon tall tank until it flooded. He is now in a 85 degree 80% humidity Tupperware container. I now realize I may not know exactly what I'm doing. How can I prevent it from flooding again? How long will he last in the container? What should I be feeding him besides the usual because of his age? Any specifics? Is he considered a baby? Any help is appreciated