Thanks Marc. I just didn't want to find a dried up froggie or something. It has foung one hell of a hiding spot.
I'll try not to worry about it much and just watch for him to come out on his own.
:assuming the frog did not escape, don't worry about it. I assume a good lid (fine mesh screen lid is best). the frog will go in the water when it wants to. the frog probably dug a hole somewhere. you aren't supposed to see them.