Yes, different alloys will cause a difference in colors.
You are going for a pretty deep blue, so I hope you are anodizing to a full 1mil.
I often match colors. Sometimes if the color is coming out too green, I'll give it a quick dunk in red, then go on with blue. Too purple, dunk in green or yellow.
I have a good eye for color, and sometime forget color tinting is a hard thing to learn.
If you think of the color wheel, with the primary and secondary colors, it might be easier to think of which direction to go.
