Got the sound of a fish formation (5)
I believe the answer is:
array
'formation' is the definition.
(I've seen this in another clue)
'got the sound of a fish' is the wordplay.
I cannot really understand how this works, but
'a' is within the answer.
'fish' could be 'ray' (ray is a kind of fish) and 'ray' is present in the answer.
A single letter 'r' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for array that I've seen before include "Matrix; arrange" , "Order - arrangement" , "Marshal" , "Impressive display; matrix" , "Matrix; display neatly" .)