LEDs and fluorescent lights don't produce spectrums that match certain color temperatures. Instead, LEDs tend to all have a big, wide peak in the blue area, and a much smaller peak in the red. Fluorescents have narrow peaks that are spread around, depending on exactly what phosphors are used. Because our eyes are relatively insensitive to red light, in order to see intense reds we need our lights to supply a big peak in the red area, making most of the LEDs we use somewhat deficient in that regards. But, if our goal is growing healthy plants, that look great in our aquascape, why do we need intense reds?