=O wow that works really really well Zogs...I dont think u need anything else to make this seem like awesome water....but I'll still post my edit in case you WANT to anyway :p
My idea with posting Fool's tile is that you looked at the way he did translucency and the botton of the sea.
...as I didnt make myself clear I made an edit
You copy all of the shading of the top of the water, *you invert the order of the ramp*(Actually dont invert it, looked at some ref and I was wrong), you take out the wavyness of the edges and you paste that to the botton.Then of course you match the lightness of each connecting side of the tile to what corresponds to each of it's walls, to communicate that it's sliced water.
With that you have some basic sense of what the botton should look like, but then you're still missing showing the mass of water that is between the botton and the top, so you want to do a gradient that goes from to completely dark at the top, to completely lit at the botton.I did that through redrawing the tile, but since (if I remember right) you work with photoshop maybe you can just apply an actual gradient :p
EDIT: took out some Irrelevant stuff I said because I found it was wrong.....suffice to say my edit isnt entirely correct, you dont have to invert the order of the ramp...you can actually use the same waves you have only darkened and making the highlights more defined and contrasted....