Hi there
I see the "fireflies" too. Mostly when I am relaxing into meditation, tai chi or reiki. I don't see aura's though.
I don't think its an astrology thing, except to the extent that water signs are supposed to be more intuitive and trust their intuition. But you can't just look at a person's sun sign, you also need to consider other elements in the chart (moon sign, ascendent etc).
I would also guess that its an "energy thing"!
Strelizia