I am not sure about the peace lily but a plant I keep in every tank is water wisteria. I leave it floating, it grows lush and bushy and the frogs LOVE to lay in it. Every morning I find most, if not all, of my frogs "sleeping" in the canopy of wisteria.

I have tons extra if you would like a couple sandwich baggies of it. I just ask that you pay for shipping.

The tank itself is looking great for a frog. Maybe a piece of driftwood leaning over the bare bottomed area (kind of leaned up at an angel in the corner) which would give another shady shot for him to lay under. They do not like bright light (they have no eye lids) which is another great reason to have a floating live or silk plant as it disperse the lighting