Fish School

In the name of Allah, the Most Gracious, the Most Merciful,

What is the plural of fish?

Fish or fishes?

Both terms are correct but are used differently.

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Fish is used when describing a multiple number of fish of the same type.

Example:
I caught 300 fish today.

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Fishes is used when we want to indicate different type of fishes.

Example:
The fishes you can buy here are salmon and tuna. We rarely have mackerel.

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Other nouns(that I know of) that follow this rule are deer and food.

Allah SWT knows best.