Hello and welcome to FF ! Not much information on Leptopelis argenteus, also known as the Silvery Tree Frog. Myself would set-up a vertical enclosure similar to a RETF set-up. IRT parameters; try to find other more common frogs from Tanzania or other habitats it uses and cross reference those. There's also a book with info on it ("Treefrogs of Africa" by Arne Schiotz); but appears to be out of print. Please share pics and good luck !