Trachycephalus resinifictrix - Milk Amazon frogs grows 3 to 3.5 in. SVL. Phyllomedusa sauvagii - Waxy Monkey frogs grows 2 to 3 in. SVL. Both species are arboreal so taller enclosures are required and the 40 gal. size recommended by Gail sounds about right. Myself would recommend a 24x18x24 in. ExoTerra as a minimum for either of your choices; and I'm certain a 36 in. tall enclosure would not go wasted by either species.

How does anyone measure the happiness level of a large tree frog in a tiny 10G enclosure ?