"How Much is the Fish?" is a hardcore/Euro-dance song by a German group Scooter.
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In May 2016, in response to increased popularity from a mention on The Tonight Show Starring Jimmy Fallon, H.P Baxxter answered the question about "How much is the fish?" on the Scooter Facebook page, revealing that "the fish" was actually the one they bought for their studio aquarium, and it cost 3.80 DM (1.94 €).[3]
https://en.wikipedia.org/wiki/How_Much_Is_the_Fish%3F