It just won't work for the long run. Maybe as a grow-out tank for 1-2 froglets. Frogs jump around quite a bit.

I've heard of experienced Dart Froggers that keep pairs of Tincs in 10 gallon tanks for years and they do alright, but that's still pushing it. I have a pair of D. tinctorius "azureus" in a 20 gallon long and they move all over the tank. Before the 20L I housed them in a 20H.