I got my babies about a week after they hatched and I bought a 60 gallon tank, but put them i a shoe box sized tupperware box inside the cage just to let them settle, now I've split the 60 gal tank in half, they each have a side with their own UTH's, and water bowls, and they don't seem any happier about the exta space than the shoe box. they point is you can house them in anything. i think with hatchlings though, it should be at least the lenth of their body. put thats just my opinion