Geovanni opened the scoring for City. Halmosi, who had hit the post with a free kick in the opening minutes, set up an easy tap-in for Dean Windass to make it 2-0 before half time.
Caleb Folan came on for the second half to face his old team, and he completed the scoring 12 minutes from time by heading in Richard Garcia's cross.
The Tigers are next in action on Saturday at Crewe.
City line-up: Matt Duke (Tony Warner, 45 mins); Bernard Mendy (Nathan Doyle, 45 mins), Michael Turner (John Welsh, 71 mins), Liam Cooper (Wayne Brown, 45 mins), Sam Ricketts (Ryan France, 67 mins); Craig Fagan (Richard Garcia, 62 mins), George Boateng (Ian Ashbee, 45 mins), Dean Marney (Nicky Featherstone, 67 mins), Peter Halmosi (Bryan Hughes, 45 mins); Dean Windass (Caleb Folan, 45 mins), Geovanni (Nick Barmby, 56 mins).