Well grown, but I'm sure there are other factors that you can't control for 100% that influence colors of the blooms. Some Phal's have fading flowers as they age. Some even start yellowish-green and are white within 1 week... others take longer to fade. I know from a cross that looks like the first on you pictured, that fades to really pale after several weeks.
Also, I've read that light intensity(during development) can change the flower color, making it more intense for instance. I'm not sure if this is true for all species/hybrids.
However, I want to address you grew great looking, beautiful flowers! Don't want to spoil the party
but imho you can't address the improvement on the fertilizer alone.
Nicole