Here is my tanning ledge. It is 12x6ft. We just finished the pool in April, but so far so good. I don' know that I would change anything about the ledge necessarily but if I did, it would be 7ft instead of 6 and also make the water depth deeper. I didn't even ask about the water depth even though it was something I researched. Just forgot! I'd say it's only about 6-8 inches deep and a few more would be nice when sitting in a lounge chair, but it's perfect as-is to just lay in it without. We don't keep a lounge chair in it currently bc we have 2 young kids who play on it with dolls, etc.
The ledge surface is the same pebble finish as the rest of the pool. At first I thought it was a little rough but I don't notice it anymore. We used a limestone paver for the coping and pool pavers and I LOVE it. It does not get hot at all, even in full Houston sun. And it is not slippery.
We also have 2 bubblers that we rarely use and an umbrella holder in the ledge.
Q