Heart's no different -- it's this water (5,3)
I believe the answer is:
north sea
'this water' is the definition.
(North Sea is an example)
'heart's no different' is the wordplay.
'different' is an anagram indicator.
'hearts'+'no'='heartsno'
'heartsno' with letters rearranged gives 'NORTH SEA'.
'it's' is the link.
(Other definitions for north sea that I've seen before include "Marine area off Britain" , "Water beside UK" , "(Formerly) German Ocean" , "Water between the UK and mainland Europe" , "Area of natural gas" .)