Tranquil holiday needed when almost at capacity (7)
I believe the answer is:
restful
'tranquil holiday' is the definition.
'restful' can be an answer for 'holiday' (thesaurus). I'm not sure about the 'tranquil' bit.
'when almost at capacity' is the wordplay.
'when' becomes 'rest' (I can't explain this - if you can you should give a lot more credence to this answer).
'almost' means to remove the last letter (most of the word but not all of it).
'at capacity' becomes 'full' (I've seen this in another clue).
'full' with its final letter removed is 'ful'.
'rest'+'ful'='RESTFUL'
'needed' is the link.
Can you help me to learn more?
(Other definitions for restful that I've seen before include "Soothing is required" , "Quiet, soothing" , "Still - calming" , "Tranquil - fluster (anag)" , "Calm" .)