mmm, probably a nice amount of time. Mine stayed in a 10X10 square enclosure for like 3 months. I moved mine into a larger tub when he was pretty young still, but cluttered it up and set it up how his other one was. The dimensions of his tub right now are...24L x 15W x 6H.

I think he'll be able to grow into it for the next couple months, I just need to up his hide size soon.