Ok. This is a strange question, but if anyone can answer it I'd be much obliged.

I recently took out my 6 month old Pacman to clean his tank and put him in a shallow plastic container with two feeder fish to eat while I worked. The container itself was completely white. A minute after placing him in it I notice he's peeing in the water, but the urine is blue! I can watch it leaving his body like that and it collects in the container turning all of the water with a light blue tint.

What in the world is going on? I can't figure out what it could be. Is he sick? And if so, what specifically caused his urine to turn blue?

I've scourged the internet looking for an answer, but haven't found anything. Does anybody have a clue as to what is going on?