That may be to much of a fan to put into a pendent, I don't know. I was thinking in terms of a hood. You don't want to cool the bulbs to much inside the pendent. They won't work very efficiently if the bulb cools off. Maybe one of the lighting gurus can jump in here.

You actually want to blow air across the surface of the water to break up the layer of humid air that forms along the surface. The drier, cooler air will increase evaporation and cooling. I think it will also help with gas exchange.