I have dove at epcot 4 times with my son and we loved it every time.
Huge diversity of fish to look at including sharks and rays. One of the turtles had to be removed because it was biting the sharks on the tail and stealing the sharks food when the sharks turned around.
They staff at Epcot give you a behind the scenes look of the aquarium and you get to dive for about 50 minutes. You actually get to become part of the attraction and the kids on the other side of the glass love to wave at you.
Lastly all the proceeds from the dive are donated to Disney’s ecology and wildlife funds around the world.
I never miss going when I am in Orlando. Please let me know if you have any other questions.