This is just plain clear acrylic which I have been working with so far.
This strip of acrylic has been sandpapered which gives it a cloudy/opaque effect. It would make the difference between the spirals very clear
This strip of acrylic has just had the sides of the acrylic drawn red with a vivid. I think this gives and effective aesthetic however if I were to use this option I would choose to use blue on the edges because it better relates to my model and its 'tornado' look.
This is a piece that was first sandpapered so that it was cloud and then I used a red vivid to colour in the piece. I then used a tissue to wipe off the excess. Because I had already sandpapered this piece it was slightly more coarse and so the ink stuck to it. This photo makes it look like the red is a solid colour however in reality the strip is slightly translucent meaning it would not be so harsh against a clear acrylic.