Fluorescent or Non-fluorescent

[Klaas]

Still very interesting this topic.
But more thoughts come up about the ultra violet spectrum.
Maybe in a small current with some airbubbles,wind on the water that create some waves,water can work like a prismaglass.
Sometimes you can see rainbowcollors trough the water on the bottom when sunlight shines on the water when the sunlight hits the water at a certain angle.
It may not the ultra violet that works ,maybe the ultra violet makes certain collors more atractive to the fish.

Klaas