Hi,
I have got a couple since New year. I hope that it is a couple because a male was already calling and he is much more little then a female. But, what colours are your frogs? When I just received mine, a female was bright green and a male - brown...Now both of them are brown, slightly green at night. Temperature 25, humidity 75%, lamp UVB....I try my best but they don't want to change.
By the way, I have them with Rhacophorus leucomystax and with Leptopelis. We can keep them with species that are the same size

. There is also Litoria Infrafrenata, that is a little different, more big that is probably also possible to mix together with Caerulea. I don't have any problems with mine. And, what is interesting, is that Racoforuses and Leptopelises change their color depending on temperature and humidity, but Litorias do not and I don't understand what they don't like. May be they are just like that. They are in good shape, eat well.
Do you frogs hide during the day? Mine go out only at night. Only Racoforuses are always visible during the day.