Make sure to keep an eye on the ambient humidity in there too...I know tanks are nice looking but in some areas of the country are impossible to keep good humidity. If you start to have issues try covering a portion of the screen lid with foil, or even get a piece of plexiglass cut to fit inside the lip of the tank. The lid would still fit over it, and it would help with some humidity.

Some people recommend damp towels, but you have to keep them wet all the time. If they dry out, they will just suck even more moisture out...

Have fun with him/her =)