The team of Marcus Hodgson, 11, Stefan Todorovic, 12, Conway Zhou, 11 and Christian Farricker, 12, broke the record that had stood since 1983 with a race time of 1:42.57.
The previous record of 1:42.80 was set by the New Canaan Y.
The relay team wasn't the only one breaking records at the meet.
Sophia Moore, 11, Ailee Mendoza, 14, Oscar Ike, 16, Eisuke Takahashi, 10, and Alex Ye, 10, all broke individual Marlins team records.
The three day event included nearly 500 swimmers, including more than 100 from the home-team Marlins. The YWCA Dolphins, New Canaan YMCA Camains and Weston Swimming also participated.
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