Yes, you can use different water planes, even on different heights, and adjust their dimensions so that they don't overlap.
If you don't like the existing presets, tweak them. I suggest you open their material and remove the cube map textures to exchange obviously unsuitable reflections with no reflections as all, which is less painful to watch. Or try your luck with default Unity water. Bottom line: Tweak those mothers tirelessly, until you end up with something you don't vigorously dislike.
Fora strikes me as linguistically more correct. However forums is more commonly accepted.
>>>>>>> Ka-Boom!
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