Hanafi
The sources give no view for it here.
طهورية ماء البحر
هل ماء البحر طاهر مطهر يصح التطهر به؟
Each school’s answer
Hanafi
Not stated in the sources
Maliki
Not stated in the sources
Shafi'i
Not stated in the sources
Hanbali
Not stated in the sources
The texts
مسألة: ماء البحر طاهر مطهر خلافا لمن منع. لقوله تعالى: {فلم تجدوا ماء فتيمموا} فعم، وقوله عليه السلام وقد سئل عن المتوضيء بمائه: (هو الطهور ماؤه) . ولأنه نوع من المياه فأشبه سائرها.
«الإشراف», al-Qadi Abd al-Wahhab p. 109
From the schools’ own books
Maliki
The sources give no view for it here.
Shafi'i
The sources give no view for it here.
Hanbali
The sources give no view for it here.
What bears this mark is in our words, our standard wording; the books’ texts stay as they are.