I don't know many of the plants yet but I would hazard a guess Ludiwigia Repens Super Red is one of the fastest red growers. I got them as green stems at about a foot tall. They converted to immersed, went red, and hit the top of the 20" high tank in just a few weeks. I've already replanted many cuttings. Mine have gotten redder since last I first posted but nothing like that deep red pic. The orange in these is beautiful too.
cl3537 is correct about the violet spectrum causing this color. Par plays a role, but more in making the coloration uniform across the leaf.
My SBReef lights with channel A cranked makes the ludwigia super red mini look like the picture you posted above, with it off it looks like your pictures, only difference is the violet/blue/cyan channels aren't there to stimulate the carotenoids and reflect the deep red color (I think that's how it works).
Channel B has red and deep red diodes in it, and they don't create the deep red coloration in the plant visually, so it's more than just adding red to make a plant redder. The violet spectrums will make the plants fluoresce in a way like corals do, at least in my experience working with it. This effect is why you see many T5-HO builds incorporate purple or actinic bulbs into their lineup because it brings out the colors to a much deeper degree visually.
Channel A on Channel B off:
Channel A off Channel B on:
