Water base colors. [?]

[Lightskin]

Hello, I have a little question. Is it even possible to change the base water color of a map, without having to make a new one?

You know, you can change the water tinting color, but still the water is not the same for The Barrens set, than for Lordaeron set. Not sure if I get to the point.

 

[fladdermasken]

You can completely change the tileset. Advanced » Modify Tileset. This will naturally affect your tiles but not the rest of your map.

 

[M0rbid]

The water tiles however are basically the same for every tileset. The difference between them is only that some are recoloured to different gradients. To control what kind of recolour you want here, you have to choose carefully when starting the map (same with the water height).
I am not totally sure how much you can adjust with the water tint later on, but it gives quite a good effect, too.

For totally natural water, I experienced Lordaeron Summer a good solution.
A forest/deep within the nature solution is most likely Ashenvale.
Barren water's standard is a brown colour that gives a great muddy effect to your surrounding.
As for underground, it is - of course- a red lavaish water, very hard to use, because it does not really loook completely like lava but also very unrealistic in normal terrains. It can has some use when set perfectly for sunrises for example.
There are some other, but I am not entirely sure about those. I remember one being pretty realistic with the right settings aswell.
Hope this helped