Carlsbad Caverns National Park is one of the premier dry caverns in the world. The lighting in the cavern was designed by an expert in theatrical lighting. When you look at the caverns with the naked eye the light is all white, no intentionally colored lights were used.
Because a wide variety of lights were used, incandescent, fluorescent, quartz, halogen, ect., and because each type of bulb/tube produces it's own spectrum of light when represented to a sensor set to daylight white balance you see the colors in these images.
Photoshop was used in the preperation of these images but nothing about any of them is a paint job.