First off, go out and buy a digital thermometer with probe and/or a temp gun (temperature gun, great for measuring surface temperature)
'Tropical' is not a measure of temperature. Also, stick on thermometers are useless. At best they measure air temperature on the side of the tank.
You need to have a basking spot surface temperature of at least 95F with a range between 95-120F being best (should have a basking spot where your dragon can move to different temperatures in that range, even with an option to climb higher to get into the high temps) Make sure you basking spot is wide and angled, to support your dragon comfortably (ideally it should be about 3-5" or more)
Second, buy a UVB bulb. This should run the length of the cage and should not be obstructed by anything (glass or fine screen). Repti glo and Repti sun are good brands.
Gaping is natural for a bearded dragon, it is how they cool down. However if the temperatures are too hot and your dragon can't get to a cooler area (ambient temp of 80F or less (cool side should be around 75-80F day time and 65-75F night, about normal room temperature..though this cool temp can be the entire cage at night, as your dragon will sleep).
As you just put him into a new tank, it will take a few days for him to get used to his new environment.
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PHLdyPayne