I got it working using a second camera and the clipping feature. It's a little complicated for such a simple thing (2 extra cameras, one for growing bottom up and one for shrinking downwards) and the positioning of the cameras when attached to a gameobjects is awkward.
Example:
Gameobject Pos: 600, 230, -5
Sprite Pos: -25, 9, 0 (Child of Gameobject, Totals to 575, 239, -5) <- hidden for normal camera. it sits in the transparentfx layer.
Then I attach the clipping camera (which only shows TransparentFX) to the gameobject because I want to make it a prefab with attached script that will increase/decrease the clipping cameras Region.height to simulate an increase/decrease in sand through its clipping.
I then need to set the transform.position of the camera to -600, -230 and the Viewport Clipping to 575, 239.
The problem with that is: If I decide to move the whole gameobject (repositioning the clock) then the clip camera will stick. It will not move with the gameobject. This makes layout horrible. Especially with multiple cameras.
Am I doing something wrong? Is there a better way?
Next idea:
I will try the newest beta with "sprite hard clipping" as soon as an admin completes my registration.