Keep with auto white balance as you can change that later. Other than that, you just blew out the highlights. You can do 1 of 2 things... You can take the picture, look at it on your screen in the camera, and adjust your exposure to -1. Or, you can shoot it in raw and bring back that detail and exposure in your raw processor. You can get this detail back by either turning down the exposure or using the recovery slider. Either way will work. Great job on slowing down the exposure to get good water softness.
