What Colour Should Iron Warriors Plasma Be?

Chat - help me out with a hobby question! I'm painting up a support squad armed with plasma guns for my Iron Warriors force. Question arising: what colour should the plasma be for Iron Warriors?

The miniature is a work in progress and categorically not complete, as can be seen from the image - no judgments on that please. But I've reached an impasse as I can't quite decided between the more obvious blues, greens, or even reds for the plasma coils. What do you think? I'd also like to have an internal "glow" where there are whites within the recesses and the colour burns out on the raised areas. A bit of a painting challenge, but I'm game. Just need to address the question of the colour first though. Recommendations welcome (as well as any tutorials that you think might help - or help other readers)!