This is my first post on StackExchange and I would like to ask a question: Is water actually blue or is that just the reflection of the sky?
It is blue. But white light needs to cross a long distance through the water to actually get the blue tint.
This related question explains it for ice, but for water it is pretty much the same story.
The ocean looks blue because red, orange and yellow (long wavelength light) are absorbed more strongly by water than is blue (short wavelength light). So when white light from the sun enters the ocean, it is mostly the blue that gets returned.