Whites Tree Frog Sleeping Behavior

Question
I got my first White's tree frog, Mario, on Friday (4/18) and 2 others on Sunday (4/20) from a different pet store.  The reptile specialist at the pet store I got Mario at believed that he was about 6-8 months old and he is around 2 inches long.  I have noticed the latter two frogs (who are slightly larger and more pudgy) are more aggressive when it comes hunting down crickets and are active and alert throughout the night.  However, Mario sleeps through most of the night as well as the day.  He seems to only be up and moving around for an hour or so during the course of the night.  I'm a bit concerned as it doesn't seem normal for him to be sleeping so much.  As for my temperatures, during the day, the the range is 88 to 75 or so.  At night, the range is 80 to 72.  I've done plenty of research on the proper conditions for these kind of frogs and I must be doing something right because the other 2 frogs are very active.  From his appearance, Mario looks very healthy.  He is a very nice, bright green with no visible sores, redness or irritation.  I don't know if this is something serious or not but I don't want to take any chances with him.  Any info you can give me would be much appreciated!

Answer
Hi Scott, I don't think you have anything to worry about at this early stage.  It can take a week or more for new animals to settle in to a normal feeding routine in a new enclosure. You will also  notice some slightly different habits and personalities between individual frogs. You didn't mention your tank size but  three whites should be housed in at least a 20 gallon tank to give them enough space and reduce food competition.
It really sounds like you have the proper husbandry and this is just a normal adjustment period.