The actual color of the water

Color of the fullscreen filter when the camera is underwater. Note you can make this more opaque with the alpha color.

How clear the water is. This is a linear slider between the refraction buffer and the baseColor of the water.

Water reflects more of the sky as the angle between it and the camera becomes greater (as it goes out into the distance). This is simulated using an approximation of Fresnel's reflection equation. The "fresnelBias" parameter indicates the minimum reflectance that the water will have. If this is set to zero, the water will not be reflective at all close to the camera.

The rate at which the water becomes more reflective as it stretches towards the horizon is exponential. This parameter sets the exponential power by which the rate changes.