It darkened up tenfold. Originally, it was very light gray. I was trying to convince myself to love it. What I was really anticipating was the charcoal tone I had seen on his previous customers pool he had done in the gray harbor. At first, I thought maybe he confused the color with the gray reef pearl, but when he came to check on it, he assured me it was the harbor gray. Once he dumped a ton of acid into the pool, it turned into the charcoal color I was looking for overnight. It is so dark, it almost looks black. It is amazing and I now truly love it.
Btw, the pic is on a slightly overcast day but it is dark even in full sunlight.