i normally keep my whites tree frogs at about 75 during the day and it drops to about 68-69 at night naturally they do have a drop in temp at night. i woulnt drap a towel over as they need humidty levels to be high but also the air needs to get into the tank. also the towel could make the temp go even higher.

i feed mine about 10-12 crickets every 2-3 days.

how young are they?

depending on the size of your tank depends on how many you can keep.

i sometimes use a moonlight but thats more to stop the temp dropping to 60 but they dont give out much heat its more so that you can watch them without disturbing them.

i always feed my wtf late at night about 9pm but i spray them 20 mins beforehand and they have realised that if i mist them late at night that they will soon be fed and they take there positions waiting for the food.

normally i mist the tank in the morning and then in the afternoon when i get home.

this is what i do with mine but i know others have there own systems when it comes to their wtf's