No red is not bad as long as it's not too much(or just red). We have had a couple of corals(Seriatopora) that has survived under just 660nm(red) for a couple of month now(for an experiment). But they doesn't look like corals you want in your tank, they are almost whiteI am definitely not trying to be sarcastic with this statement, but obviously the red light isn’t that bad then right?? Or is the Radion red a better or different type of red or something?
How much red is too much? I don't know.
/ David