The Second Vial
Blood On the Sea
Revelation 16:3
"And the Second Angel poured out his Vial upon the sea: and it became as the blood of a dead man: and every living soul died in the sea."
At the sounding of the Second Trumpet the third part of the sea became blood and the third part of the creatures which were in the sea, died and the third part of the ships were destroyed.
But here all the sea is affected. This may mean only the Sea of Galilee or the Mediterranean Sea and not the oceans.