I can totally relate to what you are having difficulty with. I cast in several competitions a year and a tick on either the forward cast or the back cast is a disqualification. A couple of years ago I was "really" having an issue with ticking.
What I found is that the bottom leg follows the tip of the rod. If I allowed the rod tip to drop after a cast it would allow the bottom leg to get closer to the water and when I started my back cast...... *tic*.
Since you are in deeper water you already have one strike against you. Plus keeping your rod tip high will greatly shorten your stroke in both directions thus making tailing loops a problem. As FK suggested you'll have to open your stance "Lefty" style and use a longer casting stroke. Casting stroke is bacically the distance your hand moves. This longer stroke will allow you to keep the fly line higher out of the water and keep your rod tip higher. Just don't allow the tip to drop "after" you make your forward false cast.