eli5: Why is water clear in small amount but blue in large amount like an ocean?

Question

I thought it might be the reflection from the sky but if that was the case, why does the ocean appears more blue the deeper you go?

In: 2918

Answer 1

An easy to see example is how glass coffee tables are clear but often have green or blue sides. The glass has a slight color and looking through the pane from the side is the thickest part.