Poor eel it, alas, is like a fish out of water (3-2-4)
I believe the answer is:
ill-at-ease
'like a fish out of water' is the definition.
(I've seen this in another clue)
'poor eel it alas' is the wordplay.
'poor' is an anagram indicator.
'eel'+'it'+'alas'='eelitalas'
'eelitalas' is an anagram of 'ILL-AT-EASE'.
'is' is the link.
(Other definitions for ill-at-ease that I've seen before include "Unsettled, anxious" , "Unsure and constrained in manner" , "Not comfortable, feeling embarrased" , "Unable to relax" , "Awkward, unsure" .)