When would you use fishes instead of fish? The same goes for fruits and any other word where a different plural form exists but the singular is most commonly used for plural. I am looking for a sentence where the singular form would be wrong and the explicit plural form must be used instead.
The following pages do not answer my question:
Irregular plurality situations in English
When is it correct to not use the irregular form for a plural? e.g. mouses vs. mice (fish & fishes)