Stretch of water’s about devoid of life, mostly after introduction of sulphur (3,3)
I believe the answer is:
red sea
'stretch of water's' is the definition.
'Red Sea' can be an answer for 'water's' (Red Sea is an example). I am not sure about the 'stretch of' bit.
'about devoid of life mostly after introduction of sulphur' is the wordplay.
I cannot really see how this works, but
'about' could be 're' ('re' means regarding or about) and 're' is present in the answer.
'sulphur' could be 's' (synonyms) and 's' is found in the answer.
The remaining letters 'dea' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for red sea that I've seen before include "One end for the Suez canal" , "It's linked to the Mediterranean by the Suez Canal" , "It divided for Moses" , "Water south of Sinai" , "Water between north Africa and Arabia" .)