A calm sky without too many clouds and low tide make this a serene capture. You can see the waves gushing through a small inlet on the left - but the force of the incoming water is not strong enough to disturb the mirror-like surface of the tidepool. The floating seaweed adds a certain dimension to the image. The setting sun casts a glow on the foreground rock - thereby accentuating the serenity of the scene.
(I must admit that this is technically not a very good composition. The setting sun is off-center although the horizon seems to follow the rule of thirds. The tidepool seems to be off-center too - but it is irregularly shaped and hence nothing much could be done about it.)
The gushing water on the left of the image would have been rendered inconsequential (too far off to the side) had the sun been centered.