For anyone who wondered, this is one of those 'tornado' swirls you get when you drain the tub.
A major thanks to my dad, for coming up with the idea of shooting this, and for helping shoot it. We cleaned out an old fish tank, set the camera inside, filled the tub, and hooked the camera up to a monitor so we could actually see what we were doing. Dad held up the light and I shot away. We had to re-fill the tub several times, since it proved to be rather difficult to get the tornado started.