Quick question - did you get this gravel from your LFS or from somewhere else? If you got it elsewhere, I would make sure it is safe to put in your tank, because of all the cloudiness.
What I would suggest is as you rinse your gravel, stir it up so all the fine stuff comes off. I know when I was washing sand it would look settled then when I would stir it it would become very cloudy again. Another thing you can do is if you have a strainer that has holes small enough, rinse the sand a little bit at a time in there.
One last idea, when you pour a glass of water out of the tap, does it have lots of little bubbles in it for a while? Might that be what you are seeing?