I think your setup looks just fine. Your water does not look too deep, and you have enough out of water areas that look easy for them to get onto. The one toad I can see in the picture looks nicely chubby too! I have 8 of these guys and they will frequently dive down and hide under the turtle docks I use in their setup for long periods of time. Long after I would have turn blue, they seem fine. These guys are tough, comical and frequently throw the rule book for normal behaviour out the window. Have fun with them!

As a side note, could you please select a country to be displayed under your user name? Thanks very much!