Yes i'm pretty sure black lights make things that are white glow. We were decorating for Halloween at work and one of the other gals wanted me to do a wall of white string art then put a black light in the hall.
I've used toe ExoTerra blue bulbs, i think they are great for evening viewing, have no clue what affect on the geckos they have though. I'm currently using one on Zoe's tank so i can see her more often. She hides alot during the day and the only way to see her is to turn out all the lights except the blue one.
Red 
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Crested Gecko Zeek:1.0
LEOS: Boo: 1.0 normal , Bronx & Nala: 1.1 blizzard,
Lily: 0.1 patternless, Abby: 0.1 albino, Zoe: 0.1 reduced pattern, Dot: 0.1 hypo
Chip: 1.0 papillion (small dog)
2.0 bettas