The film centres on a waiter working at an elite resort who finds himself being bullied by the young rich college students staying there, Variety reports.
Deciding to take revenge, he takes to a dangerous shark-ridden part of the beach before killing them one by one.
Caprica director Jonas Pate was originally signed to direct the film, Collider claims.
Schrader's most recent project is The Jesuit, which sees a framed man escape prison to exact revenge on those who have attacked his family.
The screenwriter and director is best known for his work with The Departed director Martin Scorcese, which includes Raging Bull and The Last Temptation of Christ.
Ellis's novel American Psycho was adapted for the screen with Christian Bale in the lead role.
His novels about teenagers, The Rules of Attraction and Less Than Zero, have also been turned into movies.
Schrader had planned to go to Bollywood to direct the musical action film Extreme City because of his disenchantment with the US market.
He said: "I've been getting indie movies made for 20 years. But I take a good look around and what I see is a barren, barren place - in terms of the financial community, in terms of audiences, in terms of distribution. It's cold out there."