thats odd about the spots. my frogs are in a similar size tank for two boys. waterdish, enormous snake plant and orchid moss. i mist them a few times a week, they always call right after i mist them, it's neat. or when i vacuum or have loud music. they seem to like to be misted. they get really active and start calling and eating. just checked 4 parasites and they had worms, but they are all gone now and thier color is way better.