PJ, a hydraglow is a Fluorescent blub. But the UV seamaster is not a true UV. I do however know someone with a true UV light. True UV is bad for the eyes, and that is why it can not be marketed. It also can hardly be seen by human eye. When I first saw it you could not even tell it was on until the lights were off, and even then it looked like it had dead batteries.
If it is for a presentation, I would somehow show the blue then purple then UV and explain how they are in the color spectrum. Also remember underwater red disappears first, on land red is seen the farthest.
Now if you were smart you would tell mom and dad you NEED a green UV swordlight for a school project and get on the ball!