One glow-in-the-dark animal is the swell shark. Swell sharks are shy shark species that aren't dangerous. Swell sharks are bioflourescent, which is why they glow. But that's not the only trick ...

I've been using the Shark PowerDetect Cordless Pet for a few months now ... both the LED screen and the nozzle light glow red. Once the debris is cleared and the surface is clean, the lights ...