A 10G aquarium is considered appropriate for an adult Pacman (3.5 in. or larger). Your tubs are much larger than the 10G dimensions (20Lx10Wx12H in.). For a juvenile I would consider something like the ExoTerra Breeding Box in either medium or maybe large for a bigger juvenile.

If you go with shredded coco substrate, will have to consider that when selecting enclosure height. When it comes to enclosures, it all bolts down to your needs. A hobbyist might want to have frogs in nice displays for observation while a breeder will look for efficient enclosures in regards to space and maintenance needs. Sound like you are looking for something in the middle of both options. Good luck !