I have an 8-month-old redfoot. I have the base built for a 5x6 indoor enclosure so it will last him a few years, but how tall should I make it? Would it bother him if it was too short whenever he gets bigger? He has a T8 10.0 UVB light, and I don't want that to be too far away from him. Would, say, 20 inches be fine even as he gets bigger?