Just a ten gallon tank, with a few inches of coconut fiber substrate, and a rectangular Pyrex water bowl sunk into the sub. about 2 inches deep. The key is in making sure the frog can easily get into/out of the water, and also has enough substrate to completely bury itself. Substrate needs to be kept moist, but not sopping wet, changed monthly. Here's a pic of Benny my monster female:

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2.1 Ball pythons: Goblin, Ashes, and Bela
1.0 Boa Constrictor Imperator: Apache Fog
0.1 albino Cranwell's horned frog: Bene
1.0 Tiger salamander: Slasher
1.0 black kittycat, Inky
A bunch of Oscar cichlids, one giant pleco, huge breeding lot of "fancy" (read: deformed) goldfish, and me an' the boyfriend.