With no confirmed original source, fishy fishy spread as a short soundboard clip shared for its simple, repeatable hook. The phrase plays on the English idiom for something suspicious, so listeners understand the joke without any context or setup. Its very short length made it easy to add to meme edits, reaction videos and live streams, where it works as an instant label for odd behaviour. It remains popular because the delivery is recognisable in under two seconds and fits both literal fish jokes and general suspicion gags.