Two.
Physics determines how well light travels through water. The reason everything looks blue under the ocean is because the blue portion of the light spectrum travels the best. Red is the worst. Worst to best:
Red --> Orange --> Yellow --> Green --> Blue
And while the "darkness" of your tile doesn't have anything to do with that aspect, it's not reflecting light as well as a lighter color would, so it's not helping either. This is also why your top step looks grey, your shallow end bluer, and the deep end the bluest.
But I like not only the variety of color of my LED light, but also the variety of brightness. I'll use white for watching the kids, and blues and greens for ambient light while sitting around the pool, and red for all my underwater covert missions.
And...
I didn't do much for outdoor speakers. The bass isn't great, as expected. I made one mistake, which I fixed, and live with the rest. But you can do better than I did.
I first placed my speakers under the eves and pointing at the pool. I figured the speakers would be best protected under there. But where we sit most often is right in between the speakers and pool. I also figured that made sense, so that we could hear the music best. Too best! Almost to a person guests would ask me to turn the music down! Each wanting to hear each other more than
Abba, uh, I mean Led Zeppelin. So I moved the speakers towards the pool and attached them to the edge of the patio overhang, now pointing at the pool with the table area behind. So now I can hear the music better in the water, and less at the table.
If I could, I would add more speakers in the landscaping, and point those at the pool, too. More, smaller speakers will get you better coverage in the yard than two big monsters. Two biggun's might sound better, but between guests and neighbors you might not be able to ever crank them enough to find out. If you only want to hear music, go big. If you want more coverage and more like background music, go more and smaller (and keep your neighbors happy). And if you're into bass they make woofers disguised as various things (like rocks) that you can also put in the landscaping that supposedly will shake things up (literally). Some you actually bury. Google "outdoor subwoofer" and you'll see what I mean.
Have fun with your new toys! Congrat's on the pool, it looks great (whatever color you use)!!
