Nadia, that is not in the recommended temperature range for naultinus grayii from what I understand. I think these high temperatures cause great stress for the geckos and from what I have been told constant heat like this without an area that is colder to retreat to may be detremental to your geckos health. I have heard that above 26C is shady for all naultinus. I have seen my naultinus bask under a uv bulb where the surface temperature of the basking area is 26C, but I provided this with access to area's at least 6 degrees cooler as well and they chose to sit in the heat, whether to digest or thermoregulate. A lot of keepers opt to keep their geckos outdoors in climates that resemble the climate of NZ, but I can't as things can get very hot and humid where i am in the states. I don't know if there really is that great of a difference in keeping these animals indoors or outdoors if adequate UV and airflow is provided indoors, but i would like to hear from the reluctant naultinus keepers out there on their views in regards to this. I'm sure the option to bask in direct sunlight is very beneficial, but I would not risk these animals to exposure of theivery, predation, drastic elements, or foreign pests. But like I said, the benefits must outweigh the negatives if so many outside of NZ keep their naultinus outdoors. You won't get too much help here on the forums in regards to these geckos and their husbandry, even though they seem to be hardy captives from the little experience that I have with them if kept in ideal conditions.