No, you aren't looking at a Photoshopped image, but rather a real-life lake in Australia filled with bioluminescent algae. That's right, "bioluminescence is used as a lure to attract prey by several deep sea fish such as the anglerfish." Click here for more pictures.
Dinoflagellates have an interesting twist on this mechanism. When a predator of plankton is sensed through motion in the water, the dinoflagellate luminesces. This in turn attracts even larger predators which will consume the would-be predator of the dinoflagellate.[via Philhart]