Thank you Cory! For now he's in a small plastic tub on paper towels as I don't want to scare him with too big enclosure (I'm not sure if this can happen with frogs, but it's very popular problem with young snakes so I'm doing it, haha!). In future I'd like to do more naturalistic enclosure for him (or her... for now I'm going with a boy). Our home is all the time around 80-82F, so I'm not using any additional heating in his enclosure (with all the reptiles it's easier to just keep the home at one temperature and only heat additionally the most exotic ones like ball pythons or bearded dragons.). As for feeding we tried to give him a pinky mice yesterday as the breeder told us that he should eat without problems but I guess he was stressed and didn't want to even look at it. I think I will go with the snake route, few days of leaving him totally alone (beside misting) and then we'll try to feed him. As for water we also have chinese pond turtle so some dechlorinated water is always available.
Would the same vitamins and calcium used for bearded dragons be good for this guy? We're using Repticalcium and Reptivite for them so it would be cool to just use the same for our frog.