Johnny Borizov and Jacob Nodarse are being held on murder and conspiracy charges.
Investigators say Nodarse shot and killed Jeff, Lori and Michael Kramer in their Darien home three weeks ago. Borizov is accused of being the mastermind.
Prosecutors say he wanted to get revenge on his ex-girlfriend who was inside the home but was not harmed because she hid in a closet.
Defense attorneys argued investigators had no probable cause to arrest Borizov but the judge rejected that argument.