Have you tried using the presets? They should be a quick and easy way of showing you different effects.
I see a lot of transparency, but obviously you aren't getting the depth effect kicking in. Part of your problem may be that the water isn't very deep. It looks to me like the water might be filling a very shallow area with a pretty constant depth, is that right? Try reducing the Greatest Depth setting ( might be called Transparency Dist. or something in the Windows version ). If you set it to just a little bit less than the depth of your water in the area you want to see more intense water colour then you should get a much stronger depth effect. The readout at the bottom of the View & Sculpt window will show you the depth of the water when you move the mouse over it, it's the number which comes after the "D".
The brightness of your sky and its reflection isn't really helping, it's overwhelming the water so it would be hard to see much effect in the distance anyway, if that's what you're after.
Regards,
Jo