Revelation 16:3
And the second poured out his bowl on the sea; and it became as the blood of a dead body, and every living soul died, the [creatures] in the sea.
Revelation 8:8-9
And the second angel sounded; and the appearance of a great mountain burning with fire was cast into the sea; and a third part of the sea became blood,
Revelation 11:6
These have power to shut heaven, that it may not rain in the days of their prophecy, and they have power over the waters to turn them into blood and to smite the earth with every plague as often as they will.
Revelation 10:2
and he had in his hand a little book opened. And he set his right foot on the sea, and his left on the land,
Revelation 13:1
And I stood on the sand of the sea. And I saw a beast come up out of the sea, having ten horns and seven heads, and upon his horns ten diadems, and upon his heads names of blasphemy.