99.9% of bearded dragon owners need absolutely no nighttime heat source at all. Yes, all of those "bearded dragon night bulbs" are not only unnecessary, but they also disrupt their sleep.
They come from the Australian desert, which at night becomes much cooler than the daytime temperatures, and it's pitch black! So yes, your beardie not only wants his enclosure to be considerably cooler at night than during the day, he also needs you to ditch any nighttime lights all together. AS LONG AS HIS ENCLOSURE STAYS AT 65 DEGREES AT NIGHT AT THE COOLEST, WHICH 99.9 % OF HOMES DO, YOU NEED ABSOLUTELY NO NIGHTTIME HEAT SOURCE! It's a waste of a bulb, of electricity, and it is disrupting his sleep.
If for some reason you drop the temperature in your house or apartment below 60 degrees at night (his enclosure is naturally 5-10 degrees warmer than the surrounding home temperature), which would be freezing for you at night so I highly doubt it, but if for some reason it is colder than 60 in your home at night, you should only use a very low wattage Ceramic Heat Emitter (CHE) for a nighttime heat source in his enclosure. A CHE screws into a normal lamp but emits only heat and no light, so his sleep will not be disrupted. Any of those damn "beardie night bulbs" that are red, "infrared", black, purple, or "moonlight" colored are just unnecessary garbage. In addition, beardies see in full-color, just like us, so any colored bulbs at all, day or night can cause a host of issues with their eyes and their food hunting/visibility. Only bright white basking bulbs and UVB tubes during the day for at least 14 hours each day, then 10 hours of no light or heat.