A huge crowd waiting at Main Beach saw Grimsey beat Brendan Capell by 10 seconds after swimming the 2.2km distance from Wategos Beach and after threading his way through the tail end of a record field.
He will be part of the Australian open water team which will compete at the world championships in Italy in July.
Gorman, a previous classic winner, won by 50 seconds from Danielle DeFrancesco. She, too, will be competing in Italy.
After a threatening start to the day, the swim was held in sunny conditions with swimmers enjoying crystal-clear water.
Organisers said 2041 swimmers had entered the event, with 1906 actually swimming. There were 300 entries in the mini-swim from The Pass to Main Beach.
Upwards of $40,000 is expected to be raised from the event which will go to local community and charity groups.
Full results can be accessed at Multisports Australia web-site.
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