Came clean from small fresh lake pets bathe in (5,3,5)

I believe the answer is:

spilt the beans

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'came clean' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'small fresh lake pets bathe in' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'fresh' is an anagram indicator.
'lake' becomes 'l' (geographical abbreviation).
'l'+'pets'+'bathe'+'in'='lpetsbathein'
'lpetsbathein' anagrammed gives 'piltthebeans'.
's'+'piltthebeans'='SPILT THE BEANS'

'from' is the link.

Can you help me to learn more?

I've seen this clue in The Hindu.

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