I live in Texas. Dark pools are always too warm. Dark absorbs sunlight. Bath water temp. Go light if you get a lot of strong sunlight.

The blue looks totally uninviting to me. Can't say why. It seems like a place to do physical therapy rather than have fun, relax, and swim.

The aqua it looks like actual water we have a very simple liner in aqua and the sparkle comes from the sun hitting the water that is always moving no need to have something to make it sparckle.

We don’t have pool liners where we live, mine is similar to gunite in white , looks pale aqua when filled. I prefer light colored pools, dislike garish too blue pool colors, I’ve seen some at relatives’ homes in the East Coast. Also, depth perception is compromised if too dark.

Neither one shown.
What chispa said, and K Laurence.

I had a pool liner in kind of a medium- light blue grid pattern. I wouldn’t do a pattern today, but would definitely stay in the light aqua/ blue range that is easy to see pool bottom, for stuff that oughtn’t be there and it’s best to know; for people jumping in. No dark blue, grotto drama.

Go on Pinterest and type “outdoor pool” and see the colors. The majority are a soft aqua, which seems the most inviting to dive into.