Things to remember about water color:

The blue, by and large, comes from the sky as a reflection. Up close, color is more affected by the actual color of the finish. For example, both white plaster and gray plaster with give a blue look to the pool with the gray being somewhat more intense from a distance but will look very different when viewed at poolside.

Hue, tint, and intensity will vary. Things that will have an effect on this are time of day, surrounding environment, and what distance you are viewing from.

UV rays cause fading. UV doesn't penetrate very deeply through water. The amount of blue normally found in the mix is very small, usually. I seriously doubt any fade will be noticed but inorganic blue does resist fading better. Many pools in Florida are screened in and thus, shielded from above anyway.

Scott