For a pair your looking at something along the lines of a fluval 125, but with extra filtration - ideally a cannister.
They also require a UV bulb in addition to the standard aquarium lighting
They prefer to have a relatively deep pool area that has little current along with a completely dry basking area,
They also like climbing so its best to provide them with something like redmoor wood which stretches up out of the water
Feeding wise, the best dried food by far is tetras reptominwhich contains the vitamin D and calcium etc they need, this can then be supplemented with bloodworm, brineshrimp and similar foods as well as any veg they will take. It is also best to have one or two live plants in the tank for them to snack on if they wish to do so.