NET

4 Then the third angel poured out his bowl on the rivers and the springs of water, and they turned into blood.

Darby

4 And the third poured out his bowl on the rivers, and [on] the fountains of waters; and they became^D9595 blood.

Darby Bible Notes

became - Or 'there was blood.' Ginomai. see John 1.17. Strictly 'and there was,' or 'came to be,' 'blood.' But I apprehend 'it' (ver. 3) and 'they' (ver. 4) are the sense, in spite of accuracy of grammar: blood took place as a consequence in what is spoken of. The sense is more striking as it stands in Greek considered as a vision. What he saw took that character.

KJV

4 And the third angel poured out his vial upon the rivers and fountains of waters; and they became blood.