First up, very nice picture. I like the pool-lights in particular. There is a bright/pale patch in the center of the picture - is this a radial light? I suggest you crank up the intensity of the pool lights a little and apply an overhead radial light (out of the camera view. Set the light to "disable cast shadows". It's pretty much a matter of trial and error to set lighting levels correctly IMHO. I usually find that positioning this light over the camera and off to one side slightly works well. Hope this helps